sheetjs/packages/dta/dta.ts

629 lines
19 KiB
TypeScript

import { CellObject, DenseWorkSheet, WorkBook, type utils } from 'xlsx';
export { parse, set_utils, version };
const version = "0.0.1";
let _utils: typeof utils;
/** Set internal instance of `utils`
*
* Usage:
*
* ```js
* const XLSX = require("xlsx");
* const DTA = require("dta");
* DTA.set_utils(XLSX.utils);
* ```
*
* @param utils utils object
*/
function set_utils(utils: any): void {
_utils = utils;
}
function u8_to_str(u8: Uint8Array): string {
return new TextDecoder().decode(u8);
}
/* sadly the web zealots decided to abandon binary strings */
function u8_to_latin1(u8: Uint8Array): string {
return new TextDecoder("latin1").decode(u8);
}
/* TODO: generalize and map to SSF */
function format_number_dta(value: number, format: string, t: number): CellObject {
if(value < 0) { const res = format_number_dta(-value, format, t); res.w = "-" + res.w; return res; }
const o: CellObject = { t: "n", v: value };
/* NOTE: The Stata CSV exporter appears to ignore the column formats, instead using these defaults */
switch(t) {
case 251: case 0x62: case 65530: format = "%8.0g"; break; // byte
case 252: case 0x69: case 65529: format = "%8.0g"; break; // int
case 253: case 0x6c: case 65528: format = "%12.0g"; break; // long
case 254: case 0x66: case 65527: format = "%9.0g"; break; // float
case 255: case 0x64: case 65526: format = "%10.0g"; break; // double
default: throw t;
}
try {
let w = +((format.match(/%(\d+)/)||[])[1]) || 8;
let k = 0;
if(value < 1) ++k;
if(value < 0.1) ++k;
if(value < 0.01) ++k;
if(value < 0.001) ++k;
const e = value.toExponential();
const exp = e.indexOf("e") == -1 ? 0 : +e.slice(e.indexOf("e")+1);
let h = w - 2 - exp;
if(h < 0) h = 0;
var m = format.match(/%\d+\.(\d+)/);
if(m && +m[1]) h = +m[1];
o.w = (Math.round(value * 10**(h))/10**(h)).toFixed(h).replace(/^([-]?)0\./,"$1.");
o.w = o.w.slice(0, w + k);
if(o.w.indexOf(".") > -1) o.w = o.w.replace(/0+$/,"");
o.w = o.w.replace(/\.$/,"");
if(o.w == "") o.w = "0";
} catch(e) {}
return o;
}
interface Payload {
/** Offset */
ptr: number;
/** Raw data */
raw: Uint8Array;
/** DataView */
dv: DataView;
}
function u8_to_dataview(array: Uint8Array): DataView { return new DataView(array.buffer, array.byteOffset, array.byteLength); }
function valid_inc(p: Payload, n: string): boolean {
if(u8_to_str(p.raw.slice(p.ptr, p.ptr + n.length)) != n) return false;
p.ptr += n.length;
return true;
}
function read_f64(p: Payload, LE: boolean): number | null {
p.ptr += 8;
const d = p.dv.getFloat64(p.ptr - 8, LE);
return d > 8.988e+307 ? null : d;
}
function read_f32(p: Payload, LE: boolean): number | null {
p.ptr += 4;
const d = p.dv.getFloat32(p.ptr - 4, LE);
return d > 1.701e+38 ? null : d;
}
function read_u32(p: Payload, LE: boolean) {
p.ptr += 4;
return p.dv.getUint32(p.ptr - 4, LE);
}
function read_i32(p: Payload, LE: boolean): number | null {
p.ptr += 4;
const u = p.dv.getInt32(p.ptr - 4, LE);
return u > 0x7fffffe4 ? null : u;
}
function read_u16(p: Payload, LE: boolean) {
p.ptr += 2;
return p.dv.getUint16(p.ptr - 2, LE);
}
function read_i16(p: Payload, LE: boolean): number | null {
p.ptr += 2;
const u = p.dv.getInt16(p.ptr - 2, LE);
return u > 32740 ? null : u;
}
function read_u8(p: Payload) {
return p.raw[p.ptr++];
}
function read_i8(p: Payload): number | null {
let u = p.raw[p.ptr++];
u = u < 128 ? u : u - 256;
return u > 100 ? null : u;
}
/* the annotations are from `dtaversion` */
const SUPPORTED_VERSIONS_TAGGED = [
"117", // stata 13
"118", // stata 14-18
"119", // stata 15-18 (> 32767 variables)
"120", // stata 18 (<= 32767, with aliases)
"121", // stata 18 (> 32767, with aliases)
];
const SUPPORTED_VERSIONS_LEGACY = [
102, // stata 1
103, // stata 2/3
104, // stata 4
105, // stata 5
108, // stata 6
110, // stata 7
111, // stata 7
112, // stata 8/9
113, // stata 8/9
114, // stata 10/11
115, // stata 12
];
function parse_tagged(raw: Uint8Array): WorkBook {
const err = ("Not a DTA file");
const d: Payload = {
ptr: 0,
raw,
dv: u8_to_dataview(raw)
}
let vers: number = 118;
let LE: boolean = true;
let nvar: number = 0, nobs: number = 0, nobs_lo = 0, nobs_hi = 0;
let label: string = "", timestamp: string = "";
const var_types: number[] = [];
const var_names: string[] = [];
const formats: string[] = [];
/* 5. Dataset format definition */
if(!valid_inc(d, "<stata_dta>")) throw err;
/* 5.1 Header <header> */
{
if(!valid_inc(d, "<header>")) throw err;
/* <release> */
{
if(!valid_inc(d, "<release>")) throw err;
/* NOTE: this assumes the version is 3 characters wide */
const res = u8_to_latin1(d.raw.slice(d.ptr, d.ptr+3));
d.ptr += 3;
if(!valid_inc(d, "</release>")) throw err;
if(SUPPORTED_VERSIONS_TAGGED.indexOf(res) == -1) throw (`Unsupported DTA ${res} file`);
vers = +res;
}
/* <byteorder> */
{
if(!valid_inc(d, "<byteorder>")) throw err;
/* NOTE: this assumes the byte order is 3 characters wide */
const res = u8_to_latin1(d.raw.slice(d.ptr, d.ptr+3));
d.ptr += 3;
if(!valid_inc(d, "</byteorder>")) throw err;
switch(res) {
case "MSF": LE = false; break;
case "LSF": LE = true; break;
default: throw (`Unsupported byteorder ${res}`);
}
}
/* <K> */
{
if(!valid_inc(d, "<K>")) throw err;
nvar = (vers === 119 || vers >= 121) ? read_u32(d, LE) : read_u16(d, LE);
if(!valid_inc(d, "</K>")) throw err;
}
/* <N> */
{
if(!valid_inc(d, "<N>")) throw err;
if(vers == 117) nobs = nobs_lo = read_u32(d, LE);
else {
const lo = read_u32(d, LE), hi = read_u32(d, LE);
nobs = LE ? ((nobs_lo = lo) + (nobs_hi = hi) * Math.pow(2,32)) : ((nobs_lo = hi) + (nobs_hi = lo) * Math.pow(2,32));
}
if(nobs > 1e6) console.error(`More than 1 million observations -- extra rows will be dropped`);
if(!valid_inc(d, "</N>")) throw err;
}
/* <label> */
{
if(!valid_inc(d, "<label>")) throw err;
const w = vers >= 118 ? 2 : 1;
const strlen = w == 1 ? read_u8(d) : read_u16(d, LE);
if(strlen > 0) label = u8_to_str(d.raw.slice(d.ptr, d.ptr + w));
d.ptr += strlen;
if(!valid_inc(d, "</label>")) throw err;
}
/* <timestamp> */
{
if(!valid_inc(d, "<timestamp>")) throw err;
const strlen = read_u8(d);
timestamp = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + strlen));
d.ptr += strlen;
if(!valid_inc(d, "</timestamp>")) throw err;
}
if(!valid_inc(d, "</header>")) throw err;
}
/* 5.2 Map <map> */
{
/* TODO: validate map? */
if(!valid_inc(d, "<map>")) throw err;
/* 14 8-byte offsets for:
<stata_data>
<map>
<variable_types>
<varnames>
<sortlist>
<formats>
<value_label_names>
<variable_labels>
<characteristics>
<data>
<strls>
<value_labels>
</stata_data>
EOF
*/
d.ptr += 8 * 14;
if(!valid_inc(d, "</map>")) throw err;
}
let stride = 0;
/* 5.3 Variable types <variable_types> */
{
if(!valid_inc(d, "<variable_types>")) throw err;
for(var i = 0; i < nvar; ++i) {
const type = read_u16(d, LE);
var_types.push(type);
if(type >= 1 && type <= 2045) stride += type;
else switch(type) {
case 32768: stride += 8; break;
case 65525: stride += 0; break; // alias
case 65526: stride += 8; break;
case 65527: stride += 4; break;
case 65528: stride += 4; break;
case 65529: stride += 2; break;
case 65530: stride += 1; break;
default: throw (`Unsupported field type ${type}`);
}
}
if(!valid_inc(d, "</variable_types>")) throw err;
}
/* 5.4 Variable names <varnames> */
{
if(!valid_inc(d, "<varnames>")) throw err;
const w = vers >= 118 ? 129 : 33;
for(let i = 0; i < nvar; ++i) {
const name = u8_to_str(d.raw.slice(d.ptr, d.ptr + w));
d.ptr += w;
var_names.push(name.replace(/\x00[\s\S]*/,""));
}
if(!valid_inc(d, "</varnames>")) throw err;
}
/* 5.5 Sort order of observations <sortlist> */
{
/* TODO: check sort list? */
if(!valid_inc(d, "<sortlist>")) throw err;
d.ptr += (2 * nvar + 2) * ((vers == 119 || vers == 121) ? 2 : 1);
if(!valid_inc(d, "</sortlist>")) throw err;
}
/* 5.6 Display formats <formats> */
{
if(!valid_inc(d, "<formats>")) throw err;
const w = vers >= 118 ? 57 : 49;
for(let i = 0; i < nvar; ++i) {
const name = u8_to_str(d.raw.slice(d.ptr, d.ptr + w));
d.ptr += w;
formats.push(name.replace(/\x00[\s\S]*/,""));
}
if(!valid_inc(d, "</formats>")) throw err;
}
const value_label_names: string[] = [];
/* TODO: <value_label_names> */
{
if(!valid_inc(d, "<value_label_names>")) throw err;
const w = vers >= 118 ? 129 : 33;
for(let i = 0; i < nvar; ++i, d.ptr += w) value_label_names[i] = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + w)).replace(/\x00.*$/,"");
if(!valid_inc(d, "</value_label_names>")) throw err;
}
/* TODO: <variable_labels> */
{
if(!valid_inc(d, "<variable_labels>")) throw err;
const w = vers >= 118 ? 321 : 81;
d.ptr += w * nvar;
if(!valid_inc(d, "</variable_labels>")) throw err;
}
/* 5.9 Characteristics <characteristics> */
{
if(!valid_inc(d, "<characteristics>")) throw err;
while(valid_inc(d, "<ch>")) {
const len = read_u32(d, LE);
d.ptr += len;
if(!valid_inc(d, "</ch>")) throw err;
}
if(!valid_inc(d, "</characteristics>")) throw err;
}
const ws: DenseWorkSheet = (_utils.aoa_to_sheet([var_names], {dense: true} as any) as DenseWorkSheet);
var ptrs: Array<[number, number, Uint8Array]> = []
/* 5.10 Data <data> */
{
if(!valid_inc(d, "<data>")) throw err;
for(let R = 0; R < nobs; ++R) {
const row: any[] = [];
for(let C = 0; C < nvar; ++C) {
let t = var_types[C];
// TODO: formats, dta_12{0,1} aliases?
if(t >= 1 && t <= 2045) {
/* NOTE: dta_117 restricts strf to ASCII */
let s = u8_to_str(d.raw.slice(d.ptr, d.ptr + t));
s = s.replace(/\x00[\s\S]*/,"");
row[C] = s;
d.ptr += t;
} else switch(t) {
case 65525: d.ptr += 0; break; // alias
case 65530: row[C] = read_i8(d); break; // byte
case 65529: row[C] = read_i16(d, LE); break; // int
case 65528: row[C] = read_i32(d, LE); break; // long
case 65527: row[C] = read_f32(d, LE); break; // float
case 65526: row[C] = read_f64(d, LE); break; // double
case 32768: {
row[C] = "##SheetJStrL##";
ptrs.push([R+1,C, d.raw.slice(d.ptr, d.ptr + 8)]);
d.ptr += 8;
} break;
default: throw (`Unsupported field type ${t} for ${var_names[C]}`);
}
if(typeof row[C] == "number" && formats[C]) row[C] = format_number_dta(row[C], formats[C], t);
}
_utils.sheet_add_aoa(ws, [row], {origin: -1, sheetStubs: true});
}
if(!valid_inc(d, "</data>")) throw err;
}
/* 5.11 StrLs <strls> */
{
if(!valid_inc(d, "<strls>")) throw err;
const strl_tbl: string[][] = [];
while(d.raw[d.ptr] == 71 /* G */) {
if(!valid_inc(d, "GSO")) throw err;
const v = read_u32(d, LE);
let o = 0;
if(vers == 117) o = read_u32(d, LE);
else {
const lo = read_u32(d, LE), hi = read_u32(d, LE);
o = LE ? (lo + hi * Math.pow(2,32)) : (hi + lo * Math.pow(2,32));
if(o > 1e6) console.error(`More than 1 million observations -- data will be dropped`);
}
const t = read_u8(d);
const len = read_u32(d, LE);
if(!strl_tbl[o]) strl_tbl[o] = [];
let str = "";
if(t == 129) {
// TODO: dta_117 codepage
str = new TextDecoder(vers >= 118 ? "utf8" : "latin1").decode(d.raw.slice(d.ptr, d.ptr + len));
d.ptr += len;
} else {
str = new TextDecoder(vers >= 118 ? "utf8" : "latin1").decode(d.raw.slice(d.ptr, d.ptr + len)).replace(/\x00$/,"");
d.ptr += len;
}
strl_tbl[o][v] = str;
}
if(!valid_inc(d, "</strls>")) throw err;
ptrs.forEach(([R,C,buf]) => {
const dv = u8_to_dataview(buf);
let v = 0, o = 0;
switch(vers) {
case 117: { // v(4) o(4)
v = dv.getUint32(0, LE);
o = dv.getUint32(4, LE);
} break;
case 118: case 120: { // v(2) o(6)
v = dv.getUint16(0, LE);
const o1 = dv.getUint16(2, LE), o2 = dv.getUint32(4, LE);
o = LE ? o1 + o2 * 65536 : o2 + o1 * (2**32);
} break;
case 119: case 121: { // v(3) o(5)
const v1 = dv.getUint16(0, LE), v2 = buf[2];
v = LE ? v1 + (v2 << 16) : v2 + (v1 << 8);
const o1 = buf[3], o2 = dv.getUint32(4, LE);
o = LE ? o1 + o2 * 256 : o2 + o1 * (2**32);
}
}
ws["!data"][R][C].v = strl_tbl[o][v];
});
}
/* 5.12 Value labels <value_labels> */
{
const w = vers >= 118 ? 129 : 33;
if(!valid_inc(d, "<value_labels>")) throw err;
while(valid_inc(d, "<lbl>")) {
let len = read_u32(d, LE);
const labname = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + w)).replace(/\x00.*$/,"");
d.ptr += w;
d.ptr += 3; // padding
const labels: string[] = [];
{
const n = read_u32(d, LE);
const txtlen = read_u32(d, LE);
const off: number[] = [], val: number[] = [];
for(let i = 0; i < n; ++i) off.push(read_u32(d, LE));
for(let i = 0; i < n; ++i) val.push(read_u32(d, LE));
const str = u8_to_str(d.raw.slice(d.ptr, d.ptr + txtlen));
d.ptr += txtlen;
for(let i = 0; i < n; ++i) labels[val[i]] = str.slice(off[i], str.indexOf("\x00", off[i]));
}
const C = value_label_names.indexOf(labname);
if(C == -1) throw new Error(`unexpected value label |${labname}|`);
for(let R = 1; R < ws["!data"].length; ++R) {
const cell = ws["!data"][R][C];
cell.t = "s"; cell.v = cell.w = labels[(cell.v as number)||0];
}
//d.ptr += len; // value_label_table
if(!valid_inc(d, "</lbl>")) throw err;
}
if(!valid_inc(d, "</value_labels>")) throw err;
}
if(!valid_inc(d, "</stata_dta>")) throw err;
const wb = _utils.book_new();
_utils.book_append_sheet(wb, ws, "Sheet1");
return wb;
}
function parse_legacy(raw: Uint8Array): WorkBook {
let vers: number = raw[0];
if(SUPPORTED_VERSIONS_LEGACY.indexOf(vers) == -1) throw new Error("Not a DTA file");
const d: Payload = {
ptr: 1,
raw,
dv: u8_to_dataview(raw)
}
let LE: boolean = true;
let nvar: number = 0, nobs: number = 0;
let label: string = "", timestamp: string = "";
const var_types: number[] = [];
const var_names: string[] = [];
const formats: string[] = [];
/* 5.1 Header */
{
const byteorder = read_u8(d);
switch(byteorder) {
case 1: LE = false; break;
case 2: LE = true; break;
default: throw (`DTA ${vers} Unexpected byteorder ${byteorder}`);
}
let byte = read_u8(d);
if(byte != 1) throw (`DTA ${vers} Unexpected filetype ${byte}`);
// NOTE: dta_105 technically supports filetype 2
d.ptr++; // "unused"
nvar = read_u16(d, LE);
nobs = read_u32(d, LE);
d.ptr += (vers >= 108 ? 81 : vers >= 103 ? 32 : 30); // TODO: data_label
if(vers >= 105) d.ptr += 18; // TODO: time_stamp
}
/* 5.2 Descriptors */
const value_label_names: string[] = [];
{
let C = 0;
// typlist
for(C = 0; C < nvar; ++C) var_types.push(read_u8(d));
// varlist
const w = vers >= 110 ? 33 : 9;
for(C = 0; C < nvar; ++C) {
var_names.push(u8_to_str(d.raw.slice(d.ptr, d.ptr + w)).replace(/\x00[\s\S]*$/,""));
d.ptr += w;
}
// srtlist
d.ptr += 2*(nvar + 1);
// fmtlist
const fw = (vers >= 114 ? 49 : vers >= 105 ? 12 : 7);
for(C = 0; C < nvar; ++C) {
formats.push(u8_to_str(d.raw.slice(d.ptr, d.ptr + fw)).replace(/\x00[\s\S]*$/,""));
d.ptr += fw;
}
// lbllist
const lw = vers >= 110 ? 33 : 9;
for(let i = 0; i < nvar; ++i, d.ptr += lw) value_label_names[i] = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + lw)).replace(/\x00.*$/,"");
}
/* 5.3 Variable labels */
// TODO: should these names be used in the worksheet?
d.ptr += (vers >= 106 ? 81 : 32) * nvar;
/* 5.4 Expansion fields */
if(vers >= 105) while(d.ptr < d.raw.length) {
const dt = read_u8(d), len = (vers >= 110 ? read_u32 : read_u16)(d, LE);
if(dt == 0 && len == 0) break;
d.ptr += len;
}
const ws: DenseWorkSheet = (_utils.aoa_to_sheet([var_names], {dense: true} as any) as DenseWorkSheet);
/* 5.5 Data */
for(let R = 0; R < nobs; ++R) {
const row: any[] = [];
for(let C = 0; C < nvar; ++C) {
let t = var_types[C];
// TODO: data type processing
if((vers == 111 || vers >= 113) && t >= 1 && t <= 244) {
/* NOTE: dta_117 restricts strf to ASCII */
let s = u8_to_str(d.raw.slice(d.ptr, d.ptr + t));
s = s.replace(/\x00[\s\S]*/,"");
row[C] = s;
d.ptr += t;
} else if((vers == 112 || vers <= 110) && t >= 0x80) {
/* NOTE: dta_105 restricts strf to ASCII */
let s = u8_to_str(d.raw.slice(d.ptr, d.ptr + t - 0x7F));
s = s.replace(/\x00[\s\S]*/,"");
row[C] = s;
d.ptr += t - 0x7F;
} else switch(t) {
case 251: case 0x62: row[C] = read_i8(d); break; // byte
case 252: case 0x69: row[C] = read_i16(d, LE); break; // int
case 253: case 0x6c: row[C] = read_i32(d, LE); break; // long
case 254: case 0x66: row[C] = read_f32(d, LE); break; // float
case 255: case 0x64: row[C] = read_f64(d, LE); break; // double
default: throw (`Unsupported field type ${t} for ${var_names[C]}`);
}
if(typeof row[C] == "number" && formats[C]) row[C] = format_number_dta(row[C], formats[C], t);
}
_utils.sheet_add_aoa(ws, [row], {origin: -1, sheetStubs: true});
}
/* 5.6 Value labels */
// TODO: < 115
if(vers >= 115) while(d.ptr < d.raw.length) {
const w = 33;
let len = read_u32(d, LE);
const labname = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + w)).replace(/\x00.*$/,"");
d.ptr += w;
d.ptr += 3; // padding
const labels: string[] = [];
{
const n = read_u32(d, LE);
const txtlen = read_u32(d, LE);
const off: number[] = [], val: number[] = [];
for(let i = 0; i < n; ++i) off.push(read_u32(d, LE));
for(let i = 0; i < n; ++i) val.push(read_u32(d, LE));
const str = u8_to_latin1(d.raw.slice(d.ptr, d.ptr + txtlen));
d.ptr += txtlen;
for(let i = 0; i < n; ++i) labels[val[i]] = str.slice(off[i], str.indexOf("\x00", off[i]));
}
const C = value_label_names.indexOf(labname);
if(C == -1) throw new Error(`unexpected value label |${labname}|`);
for(let R = 1; R < ws["!data"].length; ++R) {
const cell = ws["!data"][R][C];
cell.t = "s"; cell.v = cell.w = labels[(cell.v as number)||0];
}
}
const wb: WorkBook = _utils.book_new();
_utils.book_append_sheet(wb, ws, "Sheet1");
return wb;
}
/** Parse DTA file
*
* NOTE: In NodeJS, `Buffer` extends `Uint8Array`
*
* @param {Uint8Array} data File data
*/
function parse(data: Uint8Array): WorkBook {
if(data[0] >= 102 && data[0] <= 115) return parse_legacy(data);
if(data[0] === 60) return parse_tagged(data);
throw new Error("Not a DTA file");
}