Function prepareData

tfjs-vis/src/render/histogram.ts:203–224

* Formats data to the internal format used by this chart.

(data: Array<{value: number}>|number[]|
                     TypedArray)

 * Formats data to the internal format used by this chart.
 */
function prepareData(data: Array<{value: number}>|number[]|
                     TypedArray): Array<{value: number}> {
  if (data.length == null) {
    throw new Error('input data must be an array');
  }

  if (data.length === 0) {
    return [];
  } else if (typeof data[0] === 'object') {
    if ((data[0] as {value: number}).value == null) {
      throw new Error('input data must have a value field');
    } else {
      return data as Array<{value: number}>;
    }
  } else {
    const ret = Array(data.length);
    for (let i = 0; i < data.length; i++) {
      ret[i] = {value: data[i]};
    }
    return ret;
  }
}