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为什么2 .^(-4)可以运行但k=4;2 .^(-k)不能运行？
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发布于 2025-10-15 18:29:24
查看 1过去230天
问题现象
2 .^(-4)
k=4;2 .^(-k)
问题原因
整数的负指数操作不被支持。
a = 2 .^ (-4) 可以运行的原因是 Julia 自动将整数操作数（如 -4）转换为浮点数以处理负指数运算。
如果 2 是浮点数，这样也可以运行：
k = 4;a = 2.0 .^ (-k)
所属专栏：Syslab基础平台
产品信息：Syslab科学计算环境
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