This is gid.info, produced by Makeinfo version 3.12h from gid.texinfo. This is the GiD manual Copyright 1997-2002 CIMNE  File: gid.info, Node: Materials file, Next: Problem and intervals data file, Prev: Conditions file, Up: Configuration Files Materials file (.mat) --------------------- This file `NAME.mat' include originally the definition of different materials through their properties. These are base materials as they can be used as templates during the pre-processing step for the creation of newer ones. The user can define as many materials as desired and with a variable number of fields. All the unused materials will not be taken in consideration when writing the data input files for the solver. Alternatively, they can be useful to generate a materials library. Conversely to the case of conditions, the same material can be assigned to different geometrical entities levels (lines, surfaces or volumes) and even can be assigned directly to the mesh elements. In a similar way as a condition was defined, a material can be considered as a group of fields containing its name, its corresponding properties and their values. The format of the file is as follows: NUMBER: material_number MATERIAL: material_name QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value ... QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value END MATERIAL NUMBER: material_number MATERIAL: material_name ... END MATERIAL If a property of a material change depending on something (one example would be one property depending on the temperature and defined with several values for several temperatures), a table of changing values may be declared for this property. When the solver evaluates the problem, it reads the values and apply the suitable property value. The declaration of the table requires a pair of lines: First, a QUESTION line with a list of alphanumeric values between parenthesis. QUESTION: field_name:(...,optional_value_i,...) This values are the name of each of the columns in the table, and the number of values declared are the number of columns. This first line is followed by the actual data declaration: a line started with the words `VALUE: #N#' is followed by a number that indicates the quantity of elements in the matrix and, finally, the list of values. VALUE: #N# number_of_values ... value_number_i ... The number of values declared for the matrix, obviously, has to be the multiplication of the number of columns by the number of rows to be declared. The usual case of aplication of this declaration is on the thermo-mechanical simulations, where the problem is exposed to a temperature variation, and the properties of the materials change for each temperature value. All the fields must be filled with words, considering a word as a character string without any blank space amongst them. The strings signaled between quotes are literal and the ones within brackets are optional. The interface is case-sensitive, so the uppercase letters must be maintained. `Default_field_value' and different `optional_value_i' can be alphanumeric, integers or reals, depending on the type. The numbers of the materials have to be consecutive, beginning with number 1. There is no need to point out the overall number of materials or the respective number of fields for each one. This last one can be variable for each material. Note that in this file it's not permitted the inclusion of blank lines between material definitions neither between questions and values. NOTE: There are other available options to expand the capabilities of the materials window. (*note Special fields::.) * Menu: * Example Materials File creation ::  File: gid.info, Node: Example Materials File creation, Prev: Materials file, Up: Materials file Example: Creating the materials file .................................... Next is an example of a materials file creation, explained step by step: 1. Create and edit the file (`problem_type_name.mat' on this example) inside the `problem_type_name' directory (where all your problem type files are located). As you can see, except for the extension, the name of the file and the directory are the same. 2. Create the first material, which starts with these lines: NUMBER: 1 MATERIAL: Air The first number is used to index the material. Each material will be refered with one unique number (two materials can not share the same number). The second parameter is the name of the material. Again, a unique material name into this material file is required (do not use blank spaces in the name of the material.) 3. The next two lines define a property of the material and its default value: QUESTION: Density VALUE: 1.0 You can add as many properties as you want. To end the material definition, add the following line: END MATERIAL 4. In this example we have introduced some materials; the `.mat' file would be as follows: NUMBER: 1 MATERIAL: Air QUESTION: Density VALUE: 1.01 END MATERIAL NUMBER: 2 MATERIAL: Steel QUESTION: Density VALUE: 7850 END MATERIAL NUMBER: 3 MATERIAL: Aluminium QUESTION: Density VALUE: 2650 END MATERIAL NUMBER: 4 MATERIAL: Concrete QUESTION: Density VALUE: 2350 END MATERIAL NUMBER: 5 MATERIAL: Water QUESTION: Density VALUE: 997 END MATERIAL NUMBER: 6 MATERIAL: Sand QUESTION: Density VALUE: 1370 END MATERIAL 5. The management of the materials defined in the `.mat' file, is done in the Materials window (found in the Data menu), in the preprocess of GiD.  File: gid.info, Node: Problem and intervals data file, Next: Conditions symbols file, Prev: Materials file, Up: Configuration Files Problem and intervals data file (.prb) -------------------------------------- The file `NAME.prb' contains all the information about the general problem and intervals data. The general problem data is all the information required for performing the analysis and it does not concern any particular geometrical entity. This differs from the previous definitions of conditions and materials properties, which are assigned to different entities. Example of general problem data can be the type of solution algorithm used by the solver, the value of the various time steps, convergence conditions and so on. Within this data, the user may consider the definition of specific problem data (for the whole process) and intervals data (variable values along the different solution intervals). An interval would be the subdivision of a general problem that contains its own particular data. Typically, one can define a different load case for every interval or, in dynamic problems, not only variable loads, but also changing the various time steps, convergence conditions and so on. The format of the file is as follows: PROBLEM DATA QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value ... QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value END PROBLEM DATA INTERVAL DATA QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value ... QUESTION: field_name['#CB#'(...,optional_value_i,...)] VALUE: default_field_value END INTERVAL DATA All the fields must be filled with words, considering a word as a character string without any blank space amongst them. The strings signaled between quotes are literal and the ones inside brackets are optional. The interface is case-sensitive, so the uppercase letters must be maintained. `Default_field_value' and different `optional_value_i' can be alphanumeric, integers or reals, depending on the type. NOTE: There are other available options to expand the capabilities of the Problem Data window. (*note Special fields::.) * Menu: * Example Problem and intervals data file creation::  File: gid.info, Node: Example Problem and intervals data file creation, Prev: Problem and intervals data file, Up: Problem and intervals data file Example: Creating the PRB data file ................................... Next is an example of a problem data file creation, explained step by step: 1. Create and edit the file (`problem_type_name.prb' on this example) inside the `problem_type_name' directory (where all your problem type files are located). Except for the extension, the name of the file and the directory must be the same. 2. Start the file with this line: PROBLEM DATA 3. Then, add the following lines: QUESTION: Unit_System#CB#(SI,CGS,User) VALUE: SI QUESTION: Title VALUE: Default_title The first question defines a combo style menu called `Unit_System', which has the `SI' option selected by default. The second question defines a text field called `Title', and its default value is `Default_title'. 4. To finish the file, add the following line: END PROBLEM DATA 5. The whole file is as follows: PROBLEM DATA QUESTION: Unit_System#CB#(SI,CGS,User) VALUE: SI QUESTION: Title VALUE: Default_title END GENERAL DATA 6. The management of the options defined in the `.prb' file, is done in the Problem Data window (found in the Data menu), in the preprocess of GiD.  File: gid.info, Node: Conditions symbols file, Next: Unit System file, Prev: Problem and intervals data file, Up: Configuration Files Conditions symbols file (.sim) ------------------------------ This file `NAME.sim' comprises different symbols to represent some conditions during the pre-processing stage. The user may define these symbols by creating, ad hoc, geometrical drawings and the appropriate symbol will appear over the entity with the applied condition every time the user asks for it. One or more symbols can be defined for every condition and the selection will depend on the specified values in the file, which may be obtained through mathematical conditions. Also the spatial orientation can be defined in this file, depending on the values taken by the required data. For global definitions, the user must input the three components of a vector to express its spatial direction. GiD takes these values from the corresponding conditions window. The orientation of the vector can be understood as the rotation from vector (1,0,0) towards the new vector defined in the file. For line and surface conditions, the symbols may be considered as local. In this case, GiD does not consider the defined spatial orientation vector and it takes its values from the line or surface orientation. The orientation assumes vector (1,0,0) to be the corresponding entity's normal. These components, making reference to the values obtained from the adequate conditions, may include C-language expressions. They express the different field values of the mentioned condition as `cond(type,i)', where `type' (`real' or `int') makes reference to the type of variable (independent of the letters case) and `i' is the number of the field for that particular condition. * Menu: * Example Symbols File creation ::  File: gid.info, Node: Example Symbols File creation, Prev: Conditions symbols file, Up: Conditions symbols file Example: Creating the Symbols file .................................. Next is an example of a symbol file creation. Create and edit the file (`problem_type_name.sim' on this example) inside the `problem_type_name' directory (where all your problem type files are located). Except for the extension, the name of the file and the directory must be the same. The contents of the `problem_type_name.sim' example should be the following: cond Point-Constraints 3 global cond(int,5) 1 0 0 Support3D.geo global cond(int,1) && cond(int,3) 1 0 0 Support.geo global cond(int,1) || cond(int,3) cond(int,3) cond(int,1)*(-1) 0 Support-2D.geo cond Face-Load 1 local fabs(cond(real,2))+fabs(cond(real,4))+fabs(cond(real,6))>0. cond(real,2) cond(real,4) cond(real,6) Normal.geo This is a particular example of the file `.sim' where the user has defined four different symbols. Each one is read from a file `***.geo'. There is no indication of how many overall symbols are implemented. GiD simply reads all the file long through the end. The files `***.geo' are obtained through GiD. The user may design a particular drawing to symbolize a condition and this drawing will be stored as `PROBLEMNAME.geo' when saving this project as `PROBLEMNAME.gid'. The user needs not to be concerned about the symbol size but has to keep in mind that the origin corresponds to the point (0,0,0) and the reference vector is (1,0,0). Subsequently, when these files `***.geo' are invoked from `problem_type_name.sim', the symbol drawing, appears scaled on the display, at the entities location. Nevertheless, the number of symbols and consequently, the number of files `***.geo', can vary from a condition to another. In the previous example, for instance, the condition called `Point-Constraints', which is so declared by the use of `cond', comprises three different symbols. GiD knows that from the number 3 written below the condition's name. Next, GiD reads if the orientation is relative to the spatial axes (global) or moves together with its entity (local). In the example, the three symbols concerning point constraints are globally oriented. Let's imagine that this condition has six fields. First, third and fifth field values express if there exist constraints along `X-axis', `Y-axis' and `Z-axis', respectively. These values are integers and in case they were null, the concerned degree of freedom would be assumed to be unconstrained. For the first symbol, got from the file `Support3D.geo', GiD reads `cond(int,5)', or `Z-constraint'. If it is false, what means that the field's value is zero, the C-condition will not be accomplished and GiD will not draw it. Otherwise, the C-condition will be accomplished and the symbol will be invoked. When this occurs, GiD skips the rest of symbols related to this condition. Its orientation will be the same of the original drawing because the spatial vector is (1,0,0). All the considerations are valid for the second symbol, got from the file Support.geo, but now GiD has to check that both constraints (`&&'), `X-constraint' and `Y-constraint' are fixed (values different from zero). For the third symbol, got from the file `Support-2D.geo', only one of them has to be fixed (`||') and the orientation of the symbol will depend on which one is free and which one is fixed, showing on the screen the corresponding direction for both degrees of freedom. Finally, for the fourth symbol, got from the file `Normal.geo', it can be observed that the drawing of the symbol, related to the local orientation will appear scaled according to the real-type values of the second, fourth and sixth fields values. Different ways of C-language expressions are available in GiD. Thus, the last expression would be equivalent to put '`(fabs(cond(real,2))>0. || fabs(cond(real,4))!=0. || fabs(cond(real,6))>1e-10)''. *Note:* As previously mentioned, GiD internally creates a `PROJECTNAME.geo' when saving a project, where it keeps all the information about the geometry in binary format. In fact, this is the reason why the extension of these files is `.geo'. However, the file `PROJECTNAME.geo' is stored in the `PROJECTNAME.gid' directory, whereas these user-created files `***.geo' are stored in the `problem_type_name.gid' directory, being `problem_type_name' the problem's name.  File: gid.info, Node: Unit System file, Next: Special fields, Prev: Conditions symbols file, Up: Configuration Files Unit System file (.uni) ----------------------- When GiD is installed, the file `units.gid' is copied within the GiD directory. In this file it's defined a table of magnitudes. For each magnitude there is a set of units and a convertion factor between the unit and the reference unit. Also are defined the units systems. An unit system is a set of mangnitudes and the corresponding unit. BEGIN TABLE LENGTH : m {reference}, 100 cm, 1e+3 mm ... STRENGTH : kg*m/s^2 {reference}, N, 1.0e-1 kp END BEGIN SYSTEM(INTERNATIONAL) LENGTH : m MASS : kg STRENGTH : N ... TEMPERATURE : C END The syntax of the unit file (`problem_type_name.uni') within the problem type is similar. Besides, it could include the line: USER-DEFINED: ENABLED (DISABLED) meaning that the user is able (or not) to define it's own system unit within the project. If the line does not appear in the file then, it's assumed as having the value `ENABLED' If the problem type uses a property which has a unit, then GiD creates the file `project_name.uni' in the project directory. This file includes the information related to the unit used in the geometric model and the unit system used. The structure of this file is: MODEL: km PROBLEM: USER-DEFINED BEGIN SYSTEM LENGTH: m PRESSURE: Pa MASS: kg STRENGTH: N END In this file, MODEL refers to the unit of the geometric model, PROBLEM is the name of the units system used by GiD to convert all the data properties in the output to the solver. If this name is USER-DEFINED, then the system is the one defined within the file. The block BEGIN SYSTEM ... END corresponds to the user defined system.  File: gid.info, Node: Special fields, Prev: Unit System file, Up: Configuration Files Special fields -------------- These fields are useful in order to organize the information within the data files. They make the information showed on the data windows nicest and more readable. In this way the user can concentrate just on the data properties concerning the current context. * Book: With the field Book it is possible to split the data windows in other windows. For example, we can have two windows for the materials, one for the steels and another for the concretes: BOOK: Steels ... All steels come here ... BOOK: Concretes ... All concretes come here ... The same applies to conditions. For general and interval data, the field book groups a set of properties. * Title: The Title field groups a set of properties on diferent tabs of one book. All properties appearing after this field will be included on this tab. TITLE: Basic ... Basics properties .... TITLE: Advanced ... Advanced properties ... * Help: With the Help field it's posible to assign a description to the data property preceding it. In this way the user can inspect the meaning of the property throught the help context function: staying for a while with the mouse on the property or clicking the right button. QUESTION: X_flag#CB#(1,0) VALUE: 1 HELP: If this flag is set, movement is ... * Image: The Image field is useful to insert descriptive pictures on the data window. The value of this field is the file name of the picture relative to the problem type location. IMAGE: omega3.gif * Unit field: With this feature it's posible to define and work with properties having units. GiD is responsible for the convertion between units of the same magnitud. ... QUESTION: Elastic modulus XX axis:#UNITS# VALUE: 2.1E+11Pa ... * Dependencies: Depending on the value, we can define some behavior asociated to the property. For each value we can have a list of actions. The syntax is as follows: ` DEPENDENCIES:(,[TITLESTATE,,<State>],<A1>,<P1>,<NV1>,...,<An>,<Pn>,<NVn>)...(<Vm>,<Am>,<Pm>,<NVm>,...)' where: 1. <Vi> is the value that triggers the actions. A special value is #DEFAULT#, which refers to all the values not listed. 2. [TITLESTATE,<Title>,<State>] this argument is optional. Titlestate should be used to show or hide book labels. Many Titlestate can be given. <Title> is the title defined for a book (TITLE: Title). State is the visualization mode: `normal' or `hidden'. 3. <Ai> is the action and can have one of these values: SET, HIDE, RESTORE. All these actions change the value of the property with the following diferences: SET disables the property, HIDE hides the property and RESTORE brings the property to the enabled state. 4. <Pi> is the name of the property to modify. 5. <NVi> is the new value of <Pi>. A special value is #CURRENT#, which refers to the current value of <Pi>. Here is an example, ... TITLE: General QUESTION: Type_of_Analysis:#CB#(FILLING,SOLIDIFICATION) VALUE: SOLIDIFICATION DEPENDENCIES: (FILLING,TITLESTATE,Filling-Strategy,normal,RESTORE, Filling_Analysis,GRAVITY,HIDE,Solidification_Analysis,#CURRENT#) DEPENDENCIES: (SOLIDIFICATION,TITLESTATE,Filling-Strategy,hidden,HIDE, Filling_Analysis,#CURRENT#,RESTORE,Solidification_Analysis,#CURRENT#) TITLE: Filling-Strategy QUESTION: Filling_Analysis:#CB#(GRAVITY,LOW-PRESSURE,FLOW-RATE) VALUE: GRAVITY QUESTION: Solidification_Analysis:#CB#(THERMAL,THERMO-MECHANICAL) VALUE: THERMAL ... * State: Defines the state of a field. The state of a field can be `disabled', `enabled' or `hidden'. Here is an example, ... QUESTION: Elastic modulus XX axis VALUE: 2.1E+11 STATE: HIDDEN  File: gid.info, Node: Template File, Next: Executing an external program, Prev: Configuration Files, Up: Customization Template File ============= Once the user has generated the mesh, assigned the conditions and the materials properties, as well as the general problem and intervals data for the solver, it is necessary to produce the data input files to be processed by that program. To manage this reading, GiD has the capability of interpret a file called `problem_type_name.bas' (where `problem_type_name ' is the name of the working directory of the Problem Type without the `.bas' extension). This file (template file) describes the format and structure of the required data input file for the solver that is used in a particular case. This file must remain in the `problem_type_name.gid' directory, as well as the other files already described, `problem_type_name.cnd', `problem_type_name.mat', `problem_type_name.prb' and also `problem_type_name.sim' and `***.geo', if desired. In case more than one data input file is needed, GiD allows the creation of more files by means of additional files `***.bas' (note that while `problem_type_name.bas' creates an data input file named `project_name.dat', successive files `***.bas', -where `***' can be any name-, create successive files `project_name-1.dat', `project_name-2.dat' and so on), the new files follow the same rules than the ones explained next for `problem_type_name.bas'. These files work as interface from the GiD's standard results to the specific data input for any individual solver module. This allows to complete the process of running the analysis (*note Calculate::.) as one step more within the system. In case of an error in the preparation of the data input files, the programmer has only to fix the corresponding file `problem_type_name.bas' or `***.bas' and rerun the example, without having to leave GiD, recompile or, even more, reassign any data or remesh. This facility is due to the structure of the template files. They are a group of macros (like an ordinary programming language) that can be read, without need of any compiler, every time the corresponding analysis file is to be written. This ensures a fast way to debug mistakes. * Menu: * General description:: * Commands used in the .bas file:: * Detailed example::  File: gid.info, Node: General description, Next: Commands used in the .bas file, Prev: Template File, Up: Template File General description ------------------- All the rules that apply to the file `NAME.bas' are also valid for the rest of files with extension `.bas'. Thus, everything in this section will refer explicitly to the file `NAME.bas'. Any information written into this file, apart from the so-called commands, is reproduced exactly in the output file (the data input file for the numerical solver). The commands are words that begin with the character *. If the programmer wants to write an asterisk into the file he should write **. The commands are inserted among the text to be literally translated. Everyone of these commands returns one (*note Single value return commands::.) or multiple (*note Multiple values return commands::.) values obtained from the pre-processing. Other commands mimic the traditional structures to do loops or conditionals (*note Specific commands::.). It is also possible to create variables to manage some data. Comparing it to a classic programming language, the main differences will be the following: * The text is reproduced literally, without printing instructions, as it is writing-oriented. * There are no indices in the loops. When the program begins a loop, it already knows the number of iterations to perform. Furthermore, the inner variables of the loop change their values automatically. All the commands can be divided into three types: - Commands that return one single value. This value can be an integer, a real or a string. The value depends on certain values that are available to the command and on the position of the command, within the loop or after setting some other parameters. These commands can be inserted within the text and write their value where it corresponds in it. They can also appear inside an expression, what would be the example of the conditionals. For this example, the user may specify the type of the variable, integer or real, except when using `strcmp' or `strcasecmp'. If these commands are within an expression, no * should precede the command. - Commands that return more than one value. Their use is similar to that of the previously indicated commands, except for the fact that they cannot be used in other expressions. They can return different values, one after the other, depending on some values of the project. - Commands that perform loops or conditionals, create new variables, or define some specifications. The latter include condition or type of element chosen and also serve to prevent line-feeding. These commands must start at the beginning of the line and nothing will be written into the calculations file. After the command, in the same line, there can be other commands or words to complement the definitions, so, in an end of a loop or conditional, after the command the user may write what loop or conditional was finished. The arguments that appear in a command are written immediately behind it and inside parenthesis. If there are more than one, they will be separated by commas. The parenthesis might be put without any argument inside. This is useful to write something just behind the command without any separation in the middle. The arguments can be real numbers or integers, meaning the word `REAL' or the word `INT' (both in upper or lowercase) that the value to which it points has to be considered as real or integer, respectively. Other types of arguments are sometimes allowed, like the type of element, described by its name, in the command `*set elem', or a chain of characters inserted between double quotes " for the C-instructions `strcmp' and `strcasecmp'. It is also possible, sometimes, to write the field's name instead of its ordering number. EXAMPLE: Next it's showed a piece of what it could be a `.bas' file. There are two commands (*nelem and *npoint) which return the total number of elements and nodes of a project. %%%% Problem Size %%%% Number of Elements & Nodes: *nelem *npoin This `.bas' file will be converted into a `project_name.dat' file by GiD. The contents of the `project_name.dat' file could be something like this: %%%% Problem Size %%%% Number of Elements & Nodes: 5379 4678 (being 5379 the number of elements of the project, and 4678 the number of nodes)  File: gid.info, Node: Commands used in the .bas file, Next: Detailed example, Prev: General description, Up: Template File Commands used in the .bas file ------------------------------ * Menu: * Menu: * Single value return commands:: * Multiple values return commands:: * Specific commands::  File: gid.info, Node: Single value return commands, Next: Multiple values return commands, Prev: Commands used in the .bas file, Up: Commands used in the .bas file Single value return commands ............................ When writing a command, it is generally (if not explicitly mentioned) independent of the letters case, even a mixture of uppercase or lowercase would not affect the results. * *npoin, *ndime, *nnode, *nelem, *nmats. They return, respectively, the number of points, the dimension of the project being considered, the number of nodes of the element with the highest number, the number of elements and the number of materials. All of them are considered as integers and do not carry arguments (see `*format', `*intformat'), except `*nelem', which can bring different types of elements. These elements are `Linear', `Triangle', `Quadrilateral', `Tetrahedra', `Hexahedra', depending on the number of edges of the element and `All', that comprises all the possible types. The command `*nmats' returns the number of materials effectively assigned to an entity, not all the defined ones. * *GenData. It must carry an argument of integer type that specifies the number of the field to be printed. This number is the order of the field inside the general data list. This must be one of the values that are fixed for all the problem, independently of the interval (*note Problem and intervals data file::.). The field's name can also be the argument, instead, or even an abbreviation of it. The arguments `REAL' or `INT' to express the type of number for the field are also available (see `*format', `*intformat', `*realformat', `*if'). If they are not specified, the program will print a character string. It is mandatory to write one of them within an expression, except for `strcmp' and `strcasecmp'. The numeration must start with number 1. * *IntvData. The only difference with the previous one is that the field must be one of those fields varying with the interval (*note Problem and intervals data file::.). This command must be within a loop over intervals (see `*loop') and the program will automatically update the suitable value for each iteration. * *MatProp. The only difference with the previous ones is that it must be within a loop over the materials (see `*loop'). It returns the property whose field's number or name is defined by its argument. It's recommended the use of names instead of field numbers. NOTE: If argument is 0, it returns the material's name. *Caution:* If there are materials with different number of fields, the user must ensure not to print non-existent fields, using conditionals. * *Cond. The same previous remarks apply here, although now the user must notify with the command `*set' (see `*set') which is the condition being processed. It can be within a loop (see `*loop') over the different intervals in case that the conditions vary for each interval. * *ElemsNum: returns the element's number. *NodesNum: returns the node's number. *MatNum: returns the material's number. *ElemsMat: returns the number of the material assigned to the element. All of this commands must be within a proper loop (see `*loop') and change automatically for each iteration. They are considered as integers and cannot carry any argument. The number of materials will be reordered numerically, to begin from number 1 and will increase up to the number of materials assigned to any entity. * *LayerNum: returns the layer's number. *LayerName: returns the layer's name. *LayerColorRGB: returns the layer's color in RGB (three integer numbers between 0 and 256). If parameter `(1)', `(2)' or `(3)' is specified, the command returns the only the value of one color. RED is 1, GREEN is 2 and BLUE is 3. Commands *LayerName, *LayerNum and *LayerColorRGB must be inside a loop over layers; you cannot use this commands in a loop over nodes or elements. Example: *loop layers *LayerName *LayerColorRGB *Operation(LayerColorRGB(1)/255.0) *Operation(LayerColorRGB(2)/255.0) *Operation(LayerColorRGB(3)/255.0) *end layers * *NodesLayerNum: returns the layer's number. Must be used in a loop over nodes. *NodesLayerName: returns the layer's name. Must be used in a loop over nodes. *ElemsLayerNum: returns the layer's number. Must be used in a loop over elems. *ElemsLayerName: returns the layer's name. Must be used in a loop over elems. * *CondNumEntities. The user must have previously selected a condition (see `*set'). It returns the number of entities that have a condition assigned over them. * *LoopVar. This command must be inside a loop and returns, as an integer, what is considered to be the internal variable of the loop. This variable takes the value 1 in the first iteration and increases a unit for each new iteration. The parameter `elems,nodes,materials,intervals', used as argument for the corresponding loop, allows the program know which one is being processed. Otherwise, if there are nested loops, the program takes the value of the inner loop. * *Operation. It returns the result of an arithmetical expression what should be written inside parenthesis just immediately behind the command. This operation must be defined in C-format and can contain any of the commands that return one single value. The user can force the return of an integer or a real by means of the mentioned parameters `INT' or `REAL'. Otherwise, GiD returns the type according to the result. The valid C functions that can be used are: { } `+,-,*,/,(,),=,<,>,!,&,|, numbers and variables' { } `sin' { } `cos' { } `tan' { } `asin' { } `acos' { } `atan' { } `atan2' { } `exp' { } `fabs' { } `abs' { } `pow' { } `sqrt' { } `strcmp' { } `strcasecmp' The following are valid examples of operations: *operation(4*elemsnum+1) *operation(8*(loopvar-1)+1) *Note:* There cannot be blank spaces between the commands and the parenthesis that include the parameters. *Note:* Commands inside `*operation' do not need to put * at the beginning. * *LocalAxesNum. It returns the identification name of the local axes system, either when the loop is over the nodes or when it is over the elements, under a referenced condition. * *nlocalaxes. It returns the number of the defined local axes system. * *IsQuadratic. It returns the value 1 when the elements are quadratic or 0 when they are not. * *time. It returns the number of seconds elapsed since midnight. * *clock. It returns the number of clock ticks (aprox. milliseconds) of elapsed processor time. EXAMPLE: *set var t0=clock *loop nodes *nodescoord *end nodes *set var t1=clock ellapsed time=*operation((t1-t0)/1000.0) seconds  File: gid.info, Node: Multiple values return commands, Next: Specific commands, Prev: Single value return commands, Up: Commands used in the .bas file Multiple values return commands ............................... These commands return more than one value in a prescribed order, writing them one behind another. All of them, but `LocalAxesDef', are able to return one single value when a numerical argument giving the order of the value is added to the command. In this way, these commands can appear within an expression. `LocalAxesDef' or the rest of the commands without the numerical argument cannot be used inside expressions. Following, it is displayed a list of the commands with the appropriate description: * *NodesCoord. This command writes the node's coordinates. It must be inside a loop (see `*loop') over the nodes or elements. The coordinates are considered as real numbers (see `*realformat' and `*format'). It will write two or three coordinates according to the problem's dimension (see `*Ndime'). If *NodesCoord receives an argument inside a loop of nodes, this argument indicates which coordinate x, y or z must be written: Inside a loop of nodes: `*NodesCoord ' writes three or two coordinates depending on the problem's dimension. `*NodesCoord(1) ' writes the x coordinate of the actual node of the loop. `*NodesCoord(2) ' writes the y coordinate of the actual node of the loop. `*NodesCoord(3) ' writes the z coordinate of the actual node of the loop. If the argument `real' is given, the coordinates will be treated as a real number. Example: using *NodesCoord inside a loop of nodes Coordinates: Node X Y *set elems(all) *loop nodes *format "%5i%14.5e%14.5e" *NodesNum *NodesCoord(1,real) *NodesCoord(2,real) *end nodes This command effects a rundown of all the nodes of the mesh, listing their identifiers and coordinates (x and y coordinates). The contents of the `project_name.dat' file could be something like this: Coordinates: Node X Y 1 -1.28571e+001 -1.92931e+000 2 -1.15611e+001 -2.13549e+000 3 -1.26436e+001 -5.44919e-001 4 -1.06161e+001 -1.08545e+000 5 -1.12029e+001 9.22373e-002 ... *NodesCoord can also be used inside a loop of elements. In this case, it needs an additional argument that gives the local number of the node inside the element. After this argument it's also possible to give which coordinate has to be written x, y or z. Inside a loop of elements: `*NodesCoord(4) ' writes the coordinates of the 4th node of the actual element of the loop. `*NodesCoord(5,1) ' writes the x coordinate of the 5th node of the actual element of the loop. `*NodesCoord(5,2) ' writes the y coordinate of the 5th node of the actual element of the loop. `*NodesCoord(5,3) ' writes the z coordinate of the 5th node of the actual element of the loop. * *ElemsConec. This command writes the element's connectivities, i.e., the list of the nodes that belong to the element, keeping the proper sense for each case (anti-clockwise sense in 2D and depending on the standards in 3D). For shells, the user must define the sense. However, this command accepts the argument `swap' and this implies that the ordering of the nodes in quadratic elements will be inverted. The connectivities are considered as integer numbers (see `*intformat' and `*format'). *Note:* In the first versions of GiD, the optional parameter of the last command explained was `invert' instead of the present (`swap'). It was changed due to technical reasons. If you have an old `.bas' file prior to this specification, which contains this command in its previous form, when you try to export the calculation file, you will be warned about this change of use. Be aware that the output file will not be created as the user expects. * *GlobalNodes. This command returns the nodes that belong to an element's face where a condition has been defined (on the loop over the elements). The sense is the same that the sense of the element's connectivities. The returned values are considered as integer numbers (see `*intformat' and `*format'). So, the local numeration of the faces is: Triangle: 12 23 31 Quadrilateral: 12 23 34 41 Tetrahedra: 123 243 341 421 Hexahedra: 1234 1562 2673 3784 1485 5876 * *LocalNodes. The only difference with the previous one is that the returned value is the local node's numbering for the corresponding element (between 1 and `nnode)'. * *ElemsNnode. This command returns the number of nodes of the current element. (valid only inside a loop over elements) NOTE: This command is only available in GiD version 6.2.0b or newer. Example: *loop elems *ElemsNnode *end elems * *LocalAxesDef. This command returns the nine numbers that define the transformation matrix of a vector from the local axes system to the global one. Example: *loop localaxes *format "%10.4lg %* %* %10.4lg %* %* %10.4lg %* %*" x'=*LocalAxesDef *format "%* %10.4lg %* %* %10.4lg %* %* %10.4lg %*" y'=*LocalAxesDef *format "%* %* %10.4lg %* %* %10.4lg %* %* %10.4lg" z'=*LocalAxesDef *end localaxes NOTE: when `%*' is used in the `*format' command, the argument of that position is not printed. * *LocalAxesDef(EulerAngles). Last command with option `EulerAngles', returns three numbers that are the 3 Euler angles that define a local axes system. * *LocalAxesDefCenter. This command returns the origin of coordinates of the local axes defined by the user. The "Automatic" local axes do not have a center, so, the point (0,0,0) is returned. The index of the coordinate (from 1 to 3) can optionally be given to `LocalAxesDefCenter' to get the x, y or z value. Example: *LocalAxesDefCenter *LocalAxesDefCenter(1) *LocalAxesDefCenter(2) *LocalAxesDefCenter(3)