using trigonometric functions in fixed point design in vivado HLS

[sai_shashi]

Hi there,
I have an algorithm in HLS which has fixed point data types and which uses a trigonometric function:

temp=imgons[j][k] * (hls:data_t) sin(((float)(50))));

where temp and imgons are FP data types. But when i run the model i get the following error:
Can some help me? (is it the correct way to define the trigonometric function in the fixed point design ?)

Thanks in advance..

 

[vGoodtimes]

hls:data_t) is not a valid type declaration. You want (hls::data_t) for the cast.

 

[sai_shashi]

i have changed into:

temp=imgons[j][k]* (hls::data_t) sin(((float)(50)));

It gives me the following error:

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Compiling ../../../core.cpp in debug mode
In file included from C:/Xilinx/Vivado_HLS/2016.2/include/floating_point_v7_0_bitacc_cmodel.h:143:0,
                 from C:/Xilinx/Vivado_HLS/2016.2/include/hls_half.h:40,
                 from C:/Xilinx/Vivado_HLS/2016.2/include/hls/utils/x_hls_utils.h:37,
                 from C:/Xilinx/Vivado_HLS/2016.2/include/hls_math.h:48,
                 from ../../../core.h:10,
                 from ../../../core.cpp:1:
C:/Xilinx/Vivado_HLS/2016.2/include/gmp.h:62:0: warning: "__GMP_LIBGMP_DLL" redefined [enabled by default]
C:/Xilinx/Vivado_HLS/2016.2/include/floating_point_v7_0_bitacc_cmodel.h:135:0: note: this is the location of the previous definition
../../../core.cpp: In function 'void mat_3d_mult(data_t (*)[64][64], data_t (*)[64][64])':
../../../core.cpp:37:33: error: 'data_t' is not a member of 'hls'
../../../core.cpp:37:33: note: suggested alternative:
../../../core.h:31:24: note:   'data_t'
../../../core.cpp:37:46: error: expected ';' before 'sin'
make: *** [obj/core.o] Error 1
CRITICAL WARNING: [SIM 1] 'csim_design' failed: compilation error(s).

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[vGoodtimes]

These are not HLS errors. Are you sure you don't want ::data_t or <some-other-namespace>::data_t?

It sounds like you can just use (data_t) for the conversion.

 

[sai_shashi]

Hi there,

The code i am using is :

temp=imgons[j][k]* (data_t)sin(90);

where i am multiplying a matrix of ones by a constant value, sine(90)=1
but in the output i get the following values: why is it so?

 

[FvM]

Did you already learn about the difference between degree and rad? You have put sine(90 rad).