FilesExpand file tree

main

/

array.js

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

277 lines (229 loc) · 7.25 KB

main

/

array.js

Copy path

Top

File metadata and controls

• Code
• Blame

277 lines (229 loc) · 7.25 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

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

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

'use strict';

var b64decode = require('base64-arraybuffer').decode;

var isPlainObject = require('./is_plain_object');

var isArray = Array.isArray;

var ab = ArrayBuffer;

var dv = DataView;

function isTypedArray(a) {

return ab.isView(a) && !(a instanceof dv);

}

exports.isTypedArray = isTypedArray;

function isArrayOrTypedArray(a) {

return isArray(a) || isTypedArray(a);

}

exports.isArrayOrTypedArray = isArrayOrTypedArray;

/*

* Test whether an input object is 1D.

*

* Assumes we already know the object is an array.

*

* Looks only at the first element, if the dimensionality is

* not consistent we won't figure that out here.

*/

function isArray1D(a) {

return !isArrayOrTypedArray(a[0]);

}

exports.isArray1D = isArray1D;

/*

* Ensures an array has the right amount of storage space. If it doesn't

* exist, it creates an array. If it does exist, it returns it if too

* short or truncates it in-place.

*

* The goal is to just reuse memory to avoid a bit of excessive garbage

* collection.

*/

exports.ensureArray = function(out, n) {

// TODO: typed array support here? This is only used in

// traces/carpet/compute_control_points

if(!isArray(out)) out = [];

// If too long, truncate. (If too short, it will grow

// automatically so we don't care about that case)

out.length = n;

return out;

};

var typedArrays = {

u1c: typeof Uint8ClampedArray === 'undefined' ? undefined :

Uint8ClampedArray, // not supported in numpy?

i1: typeof Int8Array === 'undefined' ? undefined :

Int8Array,

u1: typeof Uint8Array === 'undefined' ? undefined :

Uint8Array,

i2: typeof Int16Array === 'undefined' ? undefined :

Int16Array,

u2: typeof Uint16Array === 'undefined' ? undefined :

Uint16Array,

i4: typeof Int32Array === 'undefined' ? undefined :

Int32Array,

u4: typeof Uint32Array === 'undefined' ? undefined :

Uint32Array,

f4: typeof Float32Array === 'undefined' ? undefined :

Float32Array,

f8: typeof Float64Array === 'undefined' ? undefined :

Float64Array,

/* TODO: potentially add Big Int

i8: typeof BigInt64Array === 'undefined' ? undefined :

BigInt64Array,

u8: typeof BigUint64Array === 'undefined' ? undefined :

BigUint64Array,

*/

};

typedArrays.uint8c = typedArrays.u1c;

typedArrays.uint8 = typedArrays.u1;

typedArrays.int8 = typedArrays.i1;

typedArrays.uint16 = typedArrays.u2;

typedArrays.int16 = typedArrays.i2;

typedArrays.uint32 = typedArrays.u4;

typedArrays.int32 = typedArrays.i4;

typedArrays.float32 = typedArrays.f4;

typedArrays.float64 = typedArrays.f8;

function isArrayBuffer(a) {

return a.constructor === ArrayBuffer;

}

exports.isArrayBuffer = isArrayBuffer;

exports.decodeTypedArraySpec = function(vIn) {

var out = [];

var v = coerceTypedArraySpec(vIn);

var dtype = v.dtype;

var T = typedArrays[dtype];

if(!T) throw new Error('Error in dtype: "' + dtype + '"');

var BYTES_PER_ELEMENT = T.BYTES_PER_ELEMENT;

var buffer = v.bdata;

if(!isArrayBuffer(buffer)) {

buffer = b64decode(buffer);

}

var shape = v.shape === undefined ?

// detect 1-d length

[buffer.byteLength / BYTES_PER_ELEMENT] :

// convert number to string and split to array

('' + v.shape).split(',');

shape.reverse(); // i.e. to match numpy order

var ndim = shape.length;

var nj, j;

var ni = +shape[0];

var rowBytes = BYTES_PER_ELEMENT * ni;

var pos = 0;

if(ndim === 1) {

out = new T(buffer);

} else if(ndim === 2) {

nj = +shape[1];

for(j = 0; j < nj; j++) {

out[j] = new T(buffer, pos, ni);

pos += rowBytes;

}

} else if(ndim === 3) {

nj = +shape[1];

var nk = +shape[2];

for(var k = 0; k < nk; k++) {

out[k] = [];

for(j = 0; j < nj; j++) {

out[k][j] = new T(buffer, pos, ni);

pos += rowBytes;

}

}

} else {

throw new Error('ndim: ' + ndim + 'is not supported with the shape:"' + v.shape + '"');

}

// attach bdata, dtype & shape to array for json export

out.bdata = v.bdata;

out.dtype = v.dtype;

out.shape = shape.reverse().join(',');

vIn._inputArray = out;

return out;

};

exports.isTypedArraySpec = function(v) {

return (

isPlainObject(v) &&

v.hasOwnProperty('dtype') && (typeof v.dtype === 'string') &&

v.hasOwnProperty('bdata') && (typeof v.bdata === 'string' || isArrayBuffer(v.bdata)) &&

(v.shape === undefined || (

v.hasOwnProperty('shape') && (typeof v.shape === 'string' || typeof v.shape === 'number')

))

);

};

function coerceTypedArraySpec(v) {

return {

bdata: v.bdata,

dtype: v.dtype,

shape: v.shape

};

}

/*

* TypedArray-compatible concatenation of n arrays

* if all arrays are the same type it will preserve that type,

* otherwise it falls back on Array.

* Also tries to avoid copying, in case one array has zero length

* But never mutates an existing array

*/

exports.concat = function() {

var args = [];

var allArray = true;

var totalLen = 0;

var _constructor, arg0, i, argi, posi, leni, out, j;

for(i = 0; i < arguments.length; i++) {

argi = arguments[i];

leni = argi.length;

if(leni) {

if(arg0) args.push(argi);

else {

arg0 = argi;

posi = leni;

}

if(isArray(argi)) {

_constructor = false;

} else {

allArray = false;

if(!totalLen) {

_constructor = argi.constructor;

} else if(_constructor !== argi.constructor) {

// TODO: in principle we could upgrade here,

// ie keep typed array but convert all to Float64Array?

_constructor = false;

}

}

totalLen += leni;

}

}

if(!totalLen) return [];

if(!args.length) return arg0;

if(allArray) return arg0.concat.apply(arg0, args);

if(_constructor) {

// matching typed arrays

out = new _constructor(totalLen);

out.set(arg0);

for(i = 0; i < args.length; i++) {

argi = args[i];

out.set(argi, posi);

posi += argi.length;

}

return out;

}

// mismatched types or Array + typed

out = new Array(totalLen);

for(j = 0; j < arg0.length; j++) out[j] = arg0[j];

for(i = 0; i < args.length; i++) {

argi = args[i];

for(j = 0; j < argi.length; j++) out[posi + j] = argi[j];

posi += j;

}

return out;

};

exports.maxRowLength = function(z) {

return _rowLength(z, Math.max, 0);

};

exports.minRowLength = function(z) {

return _rowLength(z, Math.min, Infinity);

};

function _rowLength(z, fn, len0) {

if(isArrayOrTypedArray(z)) {

if(isArrayOrTypedArray(z[0])) {

var len = len0;

for(var i = 0; i < z.length; i++) {

len = fn(len, z[i].length);

}

return len;

} else {

return z.length;

}

}

return 0;

}