如何为零以下和零以上生成非常清晰的色标？

Question

我在使用数字0 (zero)作为颜色生成比例的因素时遇到了一个大问题，接近0 (zero)的数字最终几乎变成了白色，无法看到差异。

想法是，在 0 (zero) 以上，它从绿色开始，然后变得更强，在 0 (zero) 以下，从红色开始，变得更强。

我真的需要任何数字，即使它 0.000001 已经有一个可见的绿色并且 -0.000001 有一个可见的红色。

Link 到电子表格：
https://docs.google.com/spreadsheets/d/1uN5rDEeR10m3EFw29vM_nVXGMqhLcNilYrFOQfcC97s/edit?usp=sharing

帮助图像翻译和可视化的注意事项：

Número = Number  
Nenhum = None  
Valor Máx. = Max Value
Valor Min. = Min Value

当前结果/预期结果

Answer 1

阅读您的新评论后，我了解到这些是必要条件：

零以上的值应该是绿色的（强度越超过零越远）。
低于零的值应该是红色的（强度越超过零越远）。
接近零的值应该是彩色的（不是几乎是白色的）。

鉴于这些先决条件，我开发了一个 Apps 脚本项目，该项目在您的场景中很有用。这是完整的项目：

function onOpen() {
  var ui = SpreadsheetApp.getUi();

  ui.createMenu("Extra").addItem("Generate gradient", "parseData").addToUi();
}

function parseData() {
  var darkestGreen = "#009000";
  var lighestGreen = "#B8F4B8";
  var darkestRed = "#893F45";
  var lighestRed = "#FEBFC4";
  var range = SpreadsheetApp.getActiveRange();
  var data = range.getValues();
  var biggestPositive = Math.max.apply(null, data);
  var biggestNegative = Math.min.apply(null, data);
  var greenPalette = colourPalette(darkestGreen, lighestGreen, biggestPositive);
  var redPalette = colourPalette(darkestRed, lighestRed, Math.abs(
    biggestNegative) + 1);
  var fullPalette = [];

  for (var i = 0; i < data.length; i++) {
    if (data[i] > 0) {
      var cellColour = [];

      cellColour[0] = greenPalette[data[i] - 1];
      fullPalette.push(cellColour);

    } else if (data[i] < 0) {
      var cellColour = [];

      cellColour[0] = redPalette[Math.abs(data[i]) - 1];
      fullPalette.push(cellColour);

    } else if (data[i] == 0) {
      var cellColour = [];

      cellColour[0] = null;
      fullPalette.push(cellColour);
    }
  }
  range.setBackgrounds(fullPalette);
}

function colourPalette(darkestColour, lightestColour, colourSteps) {
  var firstColour = hexToRGB(darkestColour);
  var lastColour = hexToRGB(lightestColour);
  var blending = 0.0;
  var gradientColours = [];

  for (i = 0; i < colourSteps; i++) {
    var colour = [];

    blending += (1.0 / colourSteps);
    colour[0] = firstColour[0] * blending + (1 - blending) * lastColour[0];
    colour[1] = firstColour[1] * blending + (1 - blending) * lastColour[1];
    colour[2] = firstColour[2] * blending + (1 - blending) * lastColour[2];
    gradientColours.push(rgbToHex(colour));
  }
  return gradientColours;
}

function hexToRGB(hex) {
  var colour = [];

  colour[0] = parseInt((removeNumeralSymbol(hex)).substring(0, 2), 16);
  colour[1] = parseInt((removeNumeralSymbol(hex)).substring(2, 4), 16);
  colour[2] = parseInt((removeNumeralSymbol(hex)).substring(4, 6), 16);

  return colour;
}

function removeNumeralSymbol(hex) {
  return (hex.charAt(0) == '#') ? hex.substring(1, 7) : hex
}

function rgbToHex(rgb) {
  return "#" + hex(rgb[0]) + hex(rgb[1]) + hex(rgb[2]);
}

function hex(c) {
  var pool = "0123456789abcdef";
  var integer = parseInt(c);

  if (integer == 0 || isNaN(c)) {
    return "00";
  }

  integer = Math.round(Math.min(Math.max(0, integer), 255));

  return pool.charAt((integer - integer % 16) / 16) + pool.charAt(integer % 16);
}

首先，脚本将使用 Ui class to show a customised menu called Extra. That menu calls the main function parseData, that reads the whole selection data with getValues. That function holds the darkest/lightest green/red colours. I used some colours for my example, but I advise you to edit them as you wish. Based on those colours, the function colourPalette will use graphical linear interpolation between the two colours (lightest and darkest). That interpolation will return an array with colours from darkest to lightest, with as many in-betweens as the maximum integer in the column. Please notice how the function uses many minimal functions to run repetitive tasks (converting from hexadecimal to RGB, formatting, etc…). When the palette is ready, the main function will create an array with all the used colours (meaning that it will skip unused colours, to give sharp contrast between big and small numbers). Finally, it will apply the palette using the setBackgrounds 方法。在这里您可以看到一些示例结果：

在该图片中，您可以看到每列一组颜色。在随机的小数和大数、数字系列和混合 small/big 数字之间变化。对这种方法有任何疑问，请随时提出。

如何为零以下和零以上生成非常清晰的色标？

How to generate very sharp color scale for below zero and above zero?

conditional-formatting

google-sheets