vmult_i — Multiplies a vector in a table by a scalar value.
ifn - number of the table hosting the vectorial signal to be processed
ival - scalar value to be multiplied
ielements - number of elements of the vector
idstoffset - index offset for the destination table
vmult_i multiplies each element of the vector contained in the table ifn by ival, starting from table index idstoffset. This enables you to process a specific section of a table by specifying the offset and the number of elements to be processed. Offset is counted starting from 0, so if no offset is specified (or set to 0), the table will be modified from the beginning.
This opcode runs only on initialization, there is a k-rate version of this opcode called vmult.
Negative values for idstoffset are valid. Elements from the vector that are outside the table, will be discarded, and they will not wrap around the table.
In all these opcodes, the resulting vectors are stored in ifn, overriding the intial vectors. If you want to keep initial vector, use vcopy or vcopy_i to copy it in another table. All these operators are designed to be used together with other opcodes that operate with vectorial signals such as bmscan, vcella, adsynt, adsynt2, etc. They can also be useful in conjunction with the spectral opcodes pvsftw and pvsftr.
Here is an example of the vmult_i opcode. It uses the file vmult_i.csd.
Example 500. Example of the vmult_i opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform ; Audio out Audio in -odac -iadc ;;;RT audio I/O ; For Non-realtime ouput leave only the line below: ; -o cigoto.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr=44100 ksmps=128 nchnls=2 instr 1 ifn1 = p4 ival = p5 ielements = p6 idstoffset = p7 kval init 25 vmult_i ifn1, ival, ielements, idstoffset endin instr 2 ;Printtable itable = p4 isize = ftlen(itable) kcount init 0 kval table kcount, itable printk2 kval if (kcount == isize) then turnoff endif kcount = kcount + 1 endin </CsInstruments> <CsScore> f 1 0 16 -7 1 16 17 i2 0.0 0.2 1 i1 0.4 0.01 1 2 3 4 i2 0.8 0.2 1 i1 1.0 0.01 1 0.5 5 -3 i2 1.2 0.2 1 i1 1.4 0.01 1 1.5 10 12 i2 1.6 0.2 1 e </CsScore> </CsoundSynthesizer>