memset另类初始化测试 (二)——double

前一篇：http://blog.youkuaiyun.com/synapse7/article/details/9884135

试着对double数组进行初始化？

测试代码：

#include<stdio.h>
#include<string.h>

int main(void)
{
	double db[10];
	for (int i = -4; i < 260; ++i)///已经覆盖了char的范围
	{
		memset(db, i, sizeof(db));
		printf("%4d: %e\n", i, db[0]);
	}
	return 0;
}

结果：

  -4: -1.157118e+294
  -3: -7.845912e+298
  -2: -5.314010e+303 // 最小的数
  -1: -1.#QNAN0e+000 // 溢出
   0: 0.000000e+000
   1: 7.748604e-304
   2: 5.377941e-299
   3: 3.720974e-294
   4: 2.567348e-289
   5: 1.766927e-284
   6: 1.213280e-279
   7: 8.313805e-275
   8: 5.686074e-270
   9: 3.882098e-265
  10: 2.646194e-260
  11: 1.801071e-255
  12: 1.224168e-250
  13: 8.309872e-246
  14: 5.634155e-241
  15: 3.815737e-236
  16: 2.586563e-231
  17: 1.801076e-226
  18: 1.249786e-221
  19: 8.645627e-217
  20: 5.964209e-212
  21: 4.104139e-207
  22: 2.817769e-202
  23: 1.930592e-197
  24: 1.320243e-192
  25: 9.012858e-188
  26: 6.142933e-183
  27: 4.180672e-178
  28: 2.841321e-173
  29: 1.928591e-168
  30: 1.307505e-163
  31: 8.854495e-159
  32: 6.013470e-154
  33: 4.186341e-149
  34: 2.904355e-144
  35: 2.008777e-139
  36: 1.385533e-134
  37: 9.532824e-130
  38: 6.544046e-125
  39: 4.483095e-120
  40: 3.065436e-115
  41: 2.092453e-110
  42: 1.426026e-105
  43: 9.704187e-101
  44: 6.594738e-096
  45: 4.475938e-091
  46: 3.034283e-086
  47: 2.054695e-081
  48: 1.398043e-076
  49: 9.730416e-072
  50: 6.749301e-067
  51: 4.667261e-062
  52: 3.218670e-057
  53: 2.214202e-052
  54: 1.519791e-047
  55: 1.041027e-042
  56: 7.117503e-038
  57: 4.857875e-033
  58: 3.310370e-028
  59: 2.252526e-023
  60: 1.530638e-018
  61: 1.038786e-013
  62: 7.041529e-009
  63: 4.767923e-004
  64: 3.250196e+001
  65: 2.261635e+006 // 在int范围内的一个不错的正数 
  66: 1.568421e+011
  67: 1.084396e+016 // 在long long范围内的一个不错的正数
  68: 7.477080e+020
  69: 5.142913e+025
  70: 3.529537e+030
  71: 2.417371e+035
  72: 1.652571e+040
  73: 1.127806e+045
  74: 7.684633e+049
  75: 5.228514e+054
  76: 3.552593e+059
  77: 2.410826e+064
  78: 1.634090e+069
  79: 1.106393e+074
  80: 7.556001e+078
  81: 5.256633e+083
  82: 3.644697e+088
  83: 2.519470e+093
  84: 1.736934e+098
  85: 1.194531e+103
  86: 8.196874e+107
  87: 5.613337e+112
  88: 3.836983e+117
  89: 2.618300e+122
  90: 1.783887e+127
  91: 1.213625e+132
  92: 8.245487e+136
  93: 5.595046e+141
  94: 3.792129e+146
  95: 2.567365e+151
  96: 1.756581e+156
  97: 1.221764e+161
  98: 8.469447e+165
  99: 5.853638e+170
 100: 4.034880e+175 // 一个便于记忆的大正数
 101: 2.774480e+180
 102: 1.903599e+185
 103: 1.303455e+190
 104: 8.908747e+194
 105: 6.078578e+199
 106: 4.141036e+204
 107: 2.817009e+209
 108: 1.913749e+214
 109: 1.298493e+219
 110: 8.800115e+223
 111: 5.957503e+228
 112: 4.083549e+233
 113: 2.839626e+238
 114: 1.968084e+243
 115: 1.359997e+248
 116: 9.372896e+252
 117: 6.444099e+257
 118: 4.420782e+262
 119: 3.026687e+267
 120: 2.068428e+272
 121: 1.411178e+277
 122: 9.612762e+281
 123: 6.538676e+286
 124: 4.441723e+291
 125: 3.013515e+296
 126: 2.042169e+301
 127: 1.382417e+306 // 最大的数
 128: -2.937447e-306
 129: -2.042200e-301
 130: -1.415129e-296
 131: -9.777198e-292
 132: -6.737235e-287
 133: -4.631354e-282
 134: -3.176788e-277
 135: -2.174728e-272
 136: -1.486040e-267
 137: -1.013743e-262
 138: -6.904844e-258
 139: -4.696323e-253
 140: -3.189957e-248
 141: -2.164085e-243
 142: -1.466433e-238
 143: -9.926158e-234
 144: -6.828527e-229
 145: -4.746364e-224
 146: -3.288325e-219
 147: -2.271525e-214
 148: -1.565008e-209
 149: -1.075675e-204
 150: -7.377432e-200
 151: -5.049757e-195
 152: -3.450235e-190
 153: -2.353437e-185
 154: -1.602833e-180
 155: -1.090072e-175
 156: -7.403671e-171
 157: -5.022318e-166
 158: -3.403000e-161
 159: -2.303311e-156
 160: -1.587369e-151
 161: -1.103109e-146
 162: -7.640967e-142
 163: -5.277353e-137
 164: -3.635362e-132
 165: -2.498335e-127
 166: -1.713242e-122
 167: -1.172554e-117
 168: -8.010580e-113
 169: -5.463547e-108
 170: -3.720662e-103
 171: -2.530171e-098
 172: -1.718333e-093
 173: -1.165554e-088
 174: -7.896959e-084
 175: -5.344688e-079
 176: -3.689967e-074
 177: -2.563716e-069
 178: -1.775485e-064
 179: -1.226056e-059
 180: -8.444512e-055
 181: -5.802520e-050
 182: -3.978589e-045
 183: -2.722652e-040
 184: -1.859844e-035
 185: -1.268365e-030
 186: -8.636739e-026
 187: -5.872762e-021
 188: -3.988095e-016 // long long 范围内一个不错的负数 
 189: -2.704944e-011
 190: -1.832551e-006 // int 范围内一个不错的负数
 191: -1.240196e-001
 192: -8.577506e+003
 193: -5.958214e+008
 194: -4.125540e+013
 195: -2.848394e+018
 196: -1.961541e+023
 197: -1.347656e+028
 198: -9.239234e+032
 199: -6.321913e+037
 200: -4.318036e+042 // 一个便于记忆的大负数
 201: -2.944496e+047
 202: -2.004827e+052
 203: -1.363116e+057
 204: -9.255963e+061
 205: -6.277439e+066
 206: -4.252558e+071
 207: -2.877774e+076
 208: -1.993854e+081
 209: -1.384704e+086
 210: -9.586052e+090
 211: -6.617372e+095
 212: -4.556343e+100
 213: -3.129951e+105
 214: -2.145555e+110
 215: -1.467918e+115
 216: -1.002521e+120
 217: -6.835578e+124
 218: -4.653736e+129
 219: -3.163886e+134
 220: -2.148205e+139
 221: -1.456816e+144
 222: -9.868310e+148
 223: -6.677614e+153
 224: -4.634681e+158
 225: -3.218047e+163
 226: -2.227378e+168
 227: -1.537328e+173
 228: -1.058355e+178
 229: -7.269300e+182
 230: -4.982416e+187
 231: -3.408412e+192
 232: -2.327542e+197
 233: -1.586854e+202
 234: -1.080250e+207
 235: -7.343562e+211
 236: -4.985717e+216
 237: -3.380843e+221
 238: -2.289989e+226
 239: -1.549474e+231
 240: -1.077309e+236
 241: -7.478636e+240
 242: -5.175392e+245
 243: -3.571440e+250
 244: -2.458344e+255
 245: -1.688279e+260
 246: -1.157010e+265
 247: -7.914059e+269
 248: -5.403796e+274
 249: -3.683801e+279
 250: -2.507519e+284
 251: -1.704475e+289
 252: -1.157118e+294
 253: -7.845912e+298
 254: -5.314010e+303
 255: -1.#QNAN0e+000
 256: 0.000000e+000 // 轮回
 257: 7.748604e-304
 258: 5.377941e-299
 259: 3.720974e-294