Wolfram Function Repository
Instant-use add-on functions for the Wolfram Language
Function Repository Resource:
Determine whether an expression is a dependent variable
Use DependentVariableQ to identify a variable that depends on a single variable:
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Use DependentVariableQ with a list of variables that depend on a single variable:
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Use DependentVariableQ with a variable that depends on two variables:
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These are not dependent variables:
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Define a simple function to identify all dependent variables of a single variable for a given Lagrangian and Euler-Lagrange equations:
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Lagrangian for the double pendulum:
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Lagrangian for the spherical pendulum:
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Lagrangian for the PUMA-Like Robot:
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Use DependentVars with the resource function EulerEquations to compute the corresponding Euler-Lagrange equations of motion for the Lagrangians L1, L2 and L3:
Euler-Lagrange equations for the double pendulum:
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Euler-Lagrange equations for the spherical pendulum:
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Euler-Lagrange equations for the PUMA-Like Robot:
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Use DependentVariableQ with the resource function SolutionRulesToFunctions to convert solution rules to function rules in a given list containing rules whose left-hand side don't match with a variable that depends on other variables:
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Use DependentVariableQ with the resource function SolutionRulesToFunctions on a more complicated list:
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Use DependentVariableQ with the resource function SymbolToSubscript:
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Use DependentVariableQ with the resource function FormalizeSymbols:
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DependentVariableQ only identifies dependent variables that have the formats x[var] or x[vars]:
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Wolfram Language 13.0 (December 2021) or above
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