OpenMaXwell Reference Manual

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Available directives

ADApt ADD BLOw CLEar CONvert COPy DELete DRAw END EXChange EXIt GENerate GET GOTo IF> IF< IF= INCrease ITEterate LABel LOOp MMP MOVe MULtiply PROcess REAd REFlect REName ROTate RUN SET SORt SUBtract WRIte

SUBtract data contained in one of the following files

FIEld

 

FIEld

Arguments: Name (DERived RELative)

Meaning: Read the original field or the derived field - if the argument DERived is set - of the file Name and compute the difference from the current field. Relative differences of the derived fields are computed when the argument RELative is also set.

Notes:

The current field is overwritten by the difference field.

The numbers of grid lines of both fields must be identical.

When you subtract derived fields, make sure that the fields are of the same type. A derived field consists of a real 3D vector and a scalar that is equal to the absolute value of the vector. When only one component of the vector is turned on in the Field dialog, the scalar is equal to the vector component that is turned on. In this case, the scalar may be negative. When the argument DERived is set and  RELative is not set, the differences of the vector components and the absolute value of the difference of the scalars are evaluated. In this case, the scalar may be different from the absolute value of the difference of the vectors! If RELative is set, the differences of the vectors are computed and divided by the scalar of the field contained in the file. Afterwards, the scalar is computed from the resulting "relative difference" vector, i.e., in this case, the scalar is not the relative difference of the scalars.

Special cases of Names:

 

Responsible for this web page:  Ch. Hafner, Computational Optics Group, IEF, ETH, 8092 Zurich, Switzerland

Last update 27.10.2015