整数的科学记数法 [英] Scientific notation to whole numbers

问题描述

我正在使用 XQuery 中的一些数学函数推断未来 10 年的人口增长，如下所示:

I'm extrapolating population growths 10 years in the future using some math functions in XQuery, like so:

let $db := doc("mondial.xml")

for $country in $db/mondial/country
  let $last_pop := $country/population[last()]
  let $snd_last_pop := $country/population[last() - 1]
  let $pop_growth := $last_pop div $snd_last_pop
  let $yt2026 := 2026 - $last_pop/@year

  return <country>
    {$country/name}
    <population year="2026" measured="extrap.">{
      $last_pop * math:exp($yt2026 * math:log($pop_growth))
    }</population>
  </country>

但是，我的输出要么是科学记数法，要么有很多小数位.

However, my output is either in scientific notation, or has a lot of decimal places.

<country>
  <name>Albania</name>
  <population year="2026" measured="extrap.">706860.8616776819</population>
</country>
<country>
  <name>Greece</name>
  <population year="2026" measured="extrap.">9.19404785580711E6</population>
</country>
<country>
  <name>Macedonia</name>
[...]

使用 xs:int() 会产生错误.

如何以整数显示这些值?(这个符号的名称是什么?'普通符号'?)

How do I show these values in whole numbers? (And what is the name of this notation? 'Normal notation'?)

推荐答案

您可以使用 format-number(9.19404785580711E6, "0") 强制执行没有小数位数的非科学输出.该值在返回之前四舍五入，因此给定语句的结果将是 9194048.

You can enforce non-scientific output without fractional digits using format-number(9.19404785580711E6, "0"). The value is rounded before being returned, such that the result for the given statement would be 9194048.

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