# Fungrim entry: 96f695

Symbol: ComplexBranchDerivative $\frac{d}{d z}\, f\!\left(z\right)$ Complex derivative, allowing branch cuts
The call syntax for this operator is the same as for Derivative.
This operator is equivalent to ComplexDerivative except that whereas ComplexDerivative is undefined on a branch cut (where the function is not complex differentiable), ComplexBranchDerivative gives the complex derivative of the analytically continued function across the branch cut.
Definitions:
Fungrim symbol Notation Short description
ComplexBranchDerivative$\frac{d}{d z}\, f\!\left(z\right)$ Complex derivative, allowing branch cuts
Derivative$\frac{d}{d z}\, f\!\left(z\right)$ Derivative
ComplexDerivative$\frac{d}{d z}\, f\!\left(z\right)$ Complex derivative
Source code for this entry:
Entry(ID("96f695"),
SymbolDefinition(ComplexBranchDerivative, ComplexBranchDerivative(Call(f, z), For(z, z)), "Complex derivative, allowing branch cuts"),
Description("The call syntax for this operator is the same as for", SourceForm(Derivative), "."),
Description("This operator is equivalent to", SourceForm(ComplexDerivative), "except that whereas", SourceForm(ComplexDerivative), "is undefined on a branch cut (where the function is not complex differentiable),", SourceForm(ComplexBranchDerivative), "gives the complex derivative of the analytically continued function across the branch cut."))

## Topics using this entry

Copyright (C) Fredrik Johansson and contributors. Fungrim is provided under the MIT license. The source code is on GitHub.

2021-03-15 19:12:00.328586 UTC