complex arithemtic
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Because the current version of the STx EVAL command do not support a complex data type, a package of functions is used to implement arithmetic and special handling for complex numbers.
Note:
- A numerical object containing N x M complex numbers (N>=1, M>=1), consists of 2N rows and M columns, because each complex number uses two cells of a row.
- If a numerical object containing N x M complex numbers, is converted element-wise to real numbers, the resulting object consists of N rows and M columns.
- complex -> complex
argument xc any complex type result rc same complex type as xc
rc=cr2p(xc)
- Convert xc from cartesian (real, imaginary) to polar (length, phase) format.
rc=cp2r(xc)
- Convert xc from polar (length, phase) to cartesian (real, imaginary) format.
rc=conj(xc)
- Conjugate xc; xc must be in cartesian format.
- complex -> real
argument xc any complex type result r same real type as xc
r=cr2len(xc)
- Compute length of xc; xc is stored in cartesian format.
r=cr2phi(xc)
- Compute phase of xc; xc is stored in cartesian format.
r=cget(xc,0)
- Get real part or length of xc (depends on format of xc).
r=cget(xc,1)
- Get imaginary part or phase of xc (depends on format of xc).
- real -> complex
argument x any real type argument y same type as x result rc same complex type as x
rc=cset(x,y)
- Combine elements of x (real part or length) and y (imaginary part or phase) to complex numbers.
- multiplication (element-wise)
argument xc any complex type (re,im) argument yc same type as 'xc' argument n a real or complex number (re,im) result rc same complex type as xc
rc=cmul(xc,n)
rc=cmul(n,xc)
- Multiply each element of xc with the real or complex number n.
rci,j = xci,j * n
rc=cmul(xc,yc)
- Multiply xc and yc element by element.
rci,j = xci,j * yci,j
- special functions
-
rcscalar=cdot(xcvector,ycvector)
- Compute the dot product (inner product) of the two complex vectors xc and yc (both with N elements).
rc = sumi=0..N-1 (xci * yci) , i=0..N-1
rcmatrix=ctrn(xcmatrix)
- Transposed the complex matrix xc.#
rci,j = xcj,i
rcmatrix=cmulv(xcvector,ycvector)
- Compute the tensor (or dyadic) product of the two complex vectors xc and yc:
rci,j = xci * ycj
rcvector=cmulv(xcvector,ycmatrix)
- Compute the product of the complex vector xc (N elements) and the complex matrix yc (N rows, M columns).
rcj = sumi=0..N-1 (xci * yci,j) , j=0..M-1
rcvector=cmulv(xcmatrix,ycvector)
- Compute the product of the complex matrix xc (N rows, M columns) and the complex vector yc (M elements).
rci = sumj=0..M-1 (xci,j * ycj) , i=0..N-1
rcmatrix=cmulv(xcmatrix,ycmatrix)
- Compute the product of the complex NxM matrix xc and the complex MxL matrix yc. The result is the complex NxL matrix rc.
rci,k = sumj=0..M-1 (xci,j * ycj,i) , i=0..N-1 and k=0..L-1
- See also
- fft, dft, complex numbers