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The look-up-table can generate output for different values sequentially, one per clock cycle.In my project x is a huge matrix(100 columns and 56 rows). How can I write code for these much values to put in LUT?
dear all
How can I implement log(1+exp(x)/1-exp(x)) in FPGA?suggest me the best method for this implementation. If any sample code available, please give me.
I didn't understand how to use the fixed point formats in this context.Can you please explain it?
log(1+exp(x)/1-exp(x))
In my project x is a huge matrix(100 columns and 56 rows).
Is there any sample code available to calculate log function?
Code Verilog - [expand] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 function real sin; input x; real x; real x1,y,y2,y3,y5,y7,sum,sign; begin sign = 1.0; x1 = x; if (x1<0) begin x1 = -x1; sign = -1.0; end while (x1 > 3.14159265/2.0) begin x1 = x1 - 3.14159265; sign = -1.0*sign; end y = x1*2/3.14159265; y2 = y*y; y3 = y*y2; y5 = y3*y2; y7 = y5*y2; sum = 1.570794*y - 0.645962*y3 + 0.079692*y5 - 0.004681712*y7; sin = sign*sum; end endfunction The cosine and tangent are computed from the sine: function real cos; input x; real x; begin cos = sin(x + 3.14159265/2.0); end endfunction function real tan; input x; real x; begin tan = sin(x)/cos(x); end endfunction function real rootof2; input n; integer n; real power; integer i; begin power = 0.82629586; power = power / 10000000.0; power = power + 1.0; i = -23; if (n >= 1) begin power = 2.0; i = 0; end for (i=i; i< n; i=i+1) begin power = power * power; end rootof2 = power; end endfunction function real exp; input x; real x; real x1,power,prod; integer i; begin x1 = fabs(x)*1.44269504; if (x1 > 255.0) begin exp = 0.0; if (x>0.0) begin $display("exp illegal argument:",x); $stop; end end else begin prod = 1.0; power = 128.0; for (i=7; i>=-23; i=i-1) begin if (x1 > power) begin prod = prod * rootof2(i); x1 = x1 - power; end power = power / 2.0; end if (x < 0) exp = 1.0/prod; else exp = prod; end end endfunction function real log; input x; real x; real re,log2; integer i; begin if (x <= 0.0) begin $display("log illegal argument:",x); $stop; log = 0; end else begin if (x<1.0) re = 1.0/x; else re = x; log2 = 0.0; for (i=7; i>=-23; i=i-1) begin if (re > rootof2(i)) begin re = re/rootof2(i); log2 = 2.0*log2 + 1.0; end else log2 = log2*2; end if (x < 1.0) log = -log2/12102203.16; else log = log2/12102203.16; end end endfunction function real pow; input x,y; real x,y; begin if (x<0.0) begin $display("pow illegal argument:",x); $stop; end pow = exp(y*log(x)); end endfunction function real sqrt; input x; real x; begin if (x<0.0) begin $display("sqrt illegal argument:",x); $stop; end sqrt = exp(0.5*log(x)); end endfunction function real atan; input x; real x; real x1,x2,sign,bias; real d3,s3; begin sign = 1.0; bias = 0.0; x1 = x; if (x1 < 0.0) begin x1 = -x1; sign = -1.0; end if (x1 > 1.0) begin x1 = 1.0/x1; bias = sign*3.14159265/2.0; sign = -1.0*sign; end x2 = x1*x1; d3 = x2 + 1.44863154; d3 = 0.26476862 / d3; s3 = x2 + 3.3163354; d3 = s3 - d3; d3 = 7.10676 / d3; s3 = 6.762139 + x2; d3 = s3 - d3; d3 = 3.7092563 / d3; d3 = d3 + 0.17465544; atan = sign*x1*d3+bias; end endfunction