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Improve name generation

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Marko Topolnik 2024-01-06 08:25:01 +01:00 committed by Gunnar Morling
parent e09cb7deea
commit eccc8f9097
1 changed files with 23 additions and 8 deletions
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31
src/main/java/dev/morling/onebrc/CreateMeasurements3.java
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@ -101,26 +101,41 @@ public class CreateMeasurements3 {
// Use a 7th-order curve to simulate the name length distribution.
// It gives us mostly short names, but with large outliers.
var nameLen = (int) (yOffset + factor * Math.pow(rnd.nextDouble() - xOffset, power));
minLen = Integer.min(minLen, nameLen);
maxLen = Integer.max(maxLen, nameLen);
var count = nameSource.read(buf, 0, nameLen);
if (count == -1) {
throw new Exception("Name source exhausted");
}
var name = new String(buf, 0, nameLen).trim();
while (name.length() < nameLen) {
name += readNonSpace(nameSource);
var nameBuf = new StringBuilder(nameLen);
nameBuf.append(buf, 0, nameLen);
if (Character.isWhitespace(nameBuf.charAt(0))) {
nameBuf.setCharAt(0, readNonSpace(nameSource));
}
if (Character.isWhitespace(nameBuf.charAt(nameBuf.length() - 1))) {
nameBuf.setCharAt(nameBuf.length() - 1, readNonSpace(nameSource));
}
var name = nameBuf.toString();
while (names.contains(name)) {
name = name.substring(1) + readNonSpace(nameSource);
nameBuf.setCharAt(rnd.nextInt(nameBuf.length()), readNonSpace(nameSource));
name = nameBuf.toString();
}
while (name.getBytes(StandardCharsets.UTF_8).length > 100) {
name = name.substring(0, name.length() - 1);
int actualLen;
while (true) {
actualLen = name.getBytes(StandardCharsets.UTF_8).length;
if (actualLen <= 100) {
break;
}
nameBuf.deleteCharAt(nameBuf.length() - 1);
if (Character.isWhitespace(nameBuf.charAt(nameBuf.length() - 1))) {
nameBuf.setCharAt(nameBuf.length() - 1, readNonSpace(nameSource));
}
name = nameBuf.toString();
}
if (name.indexOf(';') != -1) {
throw new Exception("Station name contains a semicolon!");
}
names.add(name);
minLen = Integer.min(minLen, actualLen);
maxLen = Integer.max(maxLen, actualLen);
var lat = Float.parseFloat(row.substring(row.indexOf(';') + 1));
// Guesstimate mean temperature using cosine of latitude
var avgTemp = (float) (30 * Math.cos(Math.toRadians(lat))) - 10;