我在导出ggvis
图时遇到问题(使用vg2png)。
一个简单的案例很有效:
library(ggvis)
mtcars %>% ggvis(x = ~hp, y = ~mpg) %>% export_png()
但是,如果我想导出分组数据,我会收到以下错误:
mtcars %>% ggvis(x = ~hp, y = ~mpg) %>% group_by(cyl) %>% export_png()
/usr/local/lib/node_modules/vega/vega.js:4799
var tx = vg.data[def.type]();
^
TypeError: Property 'treefacet' of object #<Object> is not a function
at vg.parse.transform (/usr/local/lib/node_modules/vega/vega.js:4799:29)
at Array.map (native)
at Object.vg.parse.dataflow (/usr/local/lib/node_modules/vega/vega.js:4261:34)
at /usr/local/lib/node_modules/vega/vega.js:4234:27
at Array.forEach (native)
at Object.vg.parse.data (/usr/local/lib/node_modules/vega/vega.js:4223:16)
at parse (/usr/local/lib/node_modules/vega/vega.js:4788:22)
at Object.vg.parse.spec (/usr/local/lib/node_modules/vega/vega.js:4794:23)
at Object.vg.headless.render (/usr/local/lib/node_modules/vega/vega.js:7248:12)
at render (/usr/local/lib/node_modules/vega/bin/vg2png:55:15)
你能建议我解决这个问题吗?此问题已报告here,但仍无解决方案/解决方法。
函数export_png
从ggvis对象导出PNG
或SVG
,并要求安装外部程序vg2png
。这是vega
node.js
模块的一部分。此信息来自?export_png
。