Question

嘿，我在本教程中尝试的这段代码有问题。我一直在尝试用数字预测创建一个简单的机器学习代码。

  <div v-for="(item, index) in xValues" v-bind:key="index">
        <div>

          <div class="col-sm-1">
            <input class="field field-x" v-model="xValues[index]" type="number">
            <input class="field field-y" v-model="yValues[index]" type="number">
          </div>
      </div>
      </div>

      <button class="button-add-example button--green" v-on:click="addItem">Add Value</button>
      <button class="button-train button--green" v-on:click="train">Train</button>
    </div>

    <div class="predict-controls">
      <h2 class="section col-sm-1">Predicting</h2>
      <input class="field element" v-model="valueToPredict" type="number" placeholder="Enter a number"><br>
      <div class="element" {{predictedValue}}></div>
      <button class="element button--green" v-on:click="predict" :disabled="!trained">Predict</button>
    </div>
  </div>
</template>

<script>
import * as tf from '@tensorflow/tfjs';
export default {
  data() {
    return {
      trained: false,
      xValues: [1,2,3,4,5,6],
      yValues: [1,3,5,7,9,11],
      predictedValue:'Click on train',
      valueToPredict: ''
    }
  },
  methods: {
    addItem() {
      this.xValues.push(0);
      this.yValues.push(0);
    },
    train() {
      // Define a model for linear regression.
      const model = this.model = tf.sequential();
      model.add(tf.layers.dense({units: 1, inputShape: [1]}));
      // Prepare the model for training: Specify the loss and the optimizer.
      model.compile({loss: 'meanSquaredError', optimizer: 'sgd'});
      const xs = tf.tensor2d(this.xValues, [this.xValues.length, 1]);
      const ys = tf.tensor2d(this.yValues, [this.yValues.length, 1]);
      // Train the model using the data.
      model.fit(xs, ys, {epochs: 50}).then(() => {
        this.trained = true;
        this.predictedValue = 'Ready for making predictions';
      });
    },
    predict() {
      // Use the model to do inference on a data point the model hasn't seen before:
      this.predictedValue = this.model.predict(tf.tensor2d([this.valueToPredict], [1, 1])).get(0, 0);
    }
  }
}
</script>

我收到此错误消息，但在Visual Studio中一切似乎都很好

传递给'slice2d'的参数'x'必须是数字张量，但具有字符串张量呈现页面时发生错误。检查开发人员工具控制台以获取详细信息

Answer 1

检查此行：

this.predictedValue = this.model.predict(tf.tensor2d([this.valueToPredict], [1, 1])).get(0, 0);

Tensorflow期望2d张量内的值为数字。当您从HTML输入字段中读取值时，this.valueToPredict将是一个字符串，因此会出现错误消息。

只需将您的原始值转换为数字，例如使用parseInt(this.valueToPredict)将其转换为整数即可。

Answer 2

我只需使用parseInt就能解决此错误。

   let val = parseInt(document.getElementById('inputValue').value);
   console.log(tf.tensor2d([val],[1,1]));
   document.getElementById('output').innerText = model.predict(tf.tensor2d([val],[1,1]));
});

Output for Console Log:
dataId: {}
dtype: "float32"
id: 35515
isDisposed: (...)
isDisposedInternal: false
kept: false
rank: (...)
rankType: "2"
shape: (2) [1, 1]
size: 1
strides: [1]
__proto__: Object

如何修复“必须为数字张量，但得到字符串张量”错误

2 个答案: