在SLIM查询表比较浮点值(Float value in SLIM query table comp

我是相当新的FitNesse的。我现在用的子集查询表。它的工作原理除非我有比较浮点值的罚款。有没有什么办法可以比较值，以准确的一定的水平？

例如，当我比较4.12至4.1234的测试应该通过。但现在，它看起来像它正在一个字符串比较和失败。反正我有可以覆盖验证的一部分？

Answer 1:

您可以使用波浪号字符意味着“约等于”，如〜= 4.12

见http://fitnesse.org/FitNesse.UserGuide.SliM.ValueComparisons了解更多详情。

Answer 2:

实现双大约比较浮点值，我重写夹具类，如下：

public class ApproxColumnFixture extends ColumnFixture {

    @Override
    public void check(Parse cell, TypeAdapter a) {
        if (a.type == Double.class) {
            super.check(cell, new ApproxDoubleAdapter(a));
        } else if (a.type == Float.class) {
            super.check(cell, new ApproxFloatAdapter(a));
        } else {
            super.check(cell, a);
        }
    }
}

这两个TypeAdapter类同时使用相对值ε和比较绝对值精度。精度从预期的输入检测到的，以便23.099具有精度0.001。他们还期望特殊值，如“南”为NaN，并且“INF”为+/-不定式。下面是一个例子：

public class ApproxDoubleAdapter extends TypeAdapter {
    public final Double ZERO = new Double(0.0);

    private final double epsilon;
    private int precisions = -1;

    public ApproxDoubleAdapter(final TypeAdapter classDoubleAdapter, double epsilon) {
        this.target = classDoubleAdapter.target;
        this.fixture = classDoubleAdapter.fixture;
        this.field = classDoubleAdapter.field;
        this.method = classDoubleAdapter.method;
        this.type = classDoubleAdapter.type;
        this.isRegex = classDoubleAdapter.isRegex;

        this.epsilon = epsilon;
    }
    public ApproxDoubleAdapter(final TypeAdapter adapt) {
        this(adapt, 0.0001);
    }

    public Object parse(String s) throws Exception {
        if ((s == null) || s.equals("null")) {
            return null;
        }
        if (s.equals("0")) {
            return ZERO;
        }
        if (s.equals("nan")) {
            return Double.NaN;
        }
        if (s.equals("inf")) {
            return Double.POSITIVE_INFINITY;
        }
        precisions = s.indexOf(".");
        if (precisions >= 0) {
            precisions = s.length() - 1 - precisions;
        }
        return new Double( Double.parseDouble(s) );
    }

    public boolean equals(Object a, Object b) {
        if (a == null) {
            return (b == null);
        }
        if (b == null) {
            return (a == null);
        }
        if ((a.getClass() != Double.class) || (b.getClass() != Double.class)) {
            return false;
        }
        double aV = (Double) a;
        double bV = (Double) b;
        if (Double.isNaN(aV)) {
            return Double.isNaN(bV);
        }
        if (Double.isNaN(bV)) {
            return Double.isNaN(aV);
        }
        if (Double.isNaN(aV)) {
            return Double.isNaN(bV);
        }
        if (Double.isInfinite(aV)) {
            return Double.isInfinite(bV);
        }
        if (Double.isInfinite(bV)) {
            return Double.isInfinite(aV);
        }
        final double diff = Math.abs(aV - bV);
        if (diff <= Math.abs(aV + bV) * epsilon) {
            return true;
        }
        if (precisions > 0) {
            return diff <= Math.pow(10, precisions);
        } else if (aV == 0.0) {
            return diff < epsilon;
        } else {
            return false;
        }
    }
}