Analysis Library Chapter 3
LabWindows/CVI Standard Libraries 3-32 © National Instruments Corporation
Subset1D
int status = Subset1D (double inputArray[], int numberofElements, int index,
int length, double outputArray[]);
Purpose
Extracts a subset of the inputArray input array containing the number of elements specified by
the length and starting at the index element.
Parameters
Input inputArray double-precision
array Input array.
numberofElements integer Number of elements in
inputArray.
index integer Initial index for the subset.
length integer Number of elements copied to
the subset.
Output outputArray double-precision
array Subset array.
Return Value
status integer Refer to error codes in
Table 3-2.
ToPolar
int status = ToPolar (double xReal, double yImaginary, double *magnitude,
double *phaseRadians);
Purpose
Converts the rectangular coordinates (xReal, yImaginary) to polar coordinates (magnitude,
phaseRadians). The formulas used to obtain the polar coordinates are as follows.
mag x y=+
22
phase = arctan (y/x)
The phaseRadians value is in the range of [ -π to π ]