Question

我有一个三维的numpy数组public void saveProductsDataToFile(File file) { try { JAXBContext context = JAXBContext.newInstance(ProductListWrapper.class); Marshaller m = context.createMarshaller(); m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); ProductListWrapper wrapper = new ProductListWrapper(); wrapper.setProducts(products); m.marshal(wrapper, file); setProductFilePath(file); } catch (Exception e) { Alert alert = new Alert(Alert.AlertType.ERROR); alert.setTitle("Fail!"); alert.setHeaderText("Can't save data!"); alert.setContentText("Can't save data to:\n" + file.getPath() ); alert.showAndWait(); }。我想要

public class Product {
    private StringProperty name;
    private IntegerProperty amount;
    private ProductType type;
    private BooleanProperty ifConttainsPreservatives;

    public void setType(ProductType type) {
        this.type = type;
    }

    public String getName() {
        return name.get();
    }

    public boolean isIfConttainsPreservatives() {
        return ifConttainsPreservatives.get();
    }

    public void setName(String name) {
        this.name.set(name);
    }

    public void setAmount(int amount) {
        this.amount.set(amount);
    }

    public void setIfConttainsPreservatives(boolean ifConttainsPreservatives) {
        this.ifConttainsPreservatives.set(ifConttainsPreservatives);
    }

    public ProductType getType() {

        return type;
    }

    public BooleanProperty ifConttainsPreservativesProperty() {
        return ifConttainsPreservatives;
    }

    public StringProperty nameProperty() {
        return name;
    }

    public int getAmount() {
        return amount.get();
    }

    public IntegerProperty amountProperty() {
        return amount;
    }

    public Product(int amount, boolean ifContainsPreservatives, String name, ProductType type) {
        this.name = new SimpleStringProperty(name);
        this.amount = new SimpleIntegerProperty(amount);
        this.ifConttainsPreservatives = new SimpleBooleanProperty(ifContainsPreservatives);
        this.type =type;
    }

    public Product() {
    }
}

每个A

。

我怎样才能在numpy中优雅地做到这一点？是否可以避免所有A[i, i, :] = 1.0循环？

Answer 1

方法＃1 您可以使用np.eye创建对角线遮罩，然后使用布尔索引来指定 -

mask = np.eye(A.shape[0], dtype=bool)
A[mask] = 1.0

方法＃2 使用基于整数的索引 -

r = np.arange(A.shape[0])
A[r,r] = 1.0

方法＃3 重塑为2D，然后分配到行中 -

n = A.shape[0]
A.reshape(-1,A.shape[-1])[np.arange(n)*(n+1)] = 1.0

如何填充＆＃34;部分对角轴＆＃34;一个numpy数组

1 个答案: