我有一个类似于下面所示的数据表，我希望使用data.table中的RStudio进行修改。
library(data.table)
set.seed(57)
DT <- data.table(ITEM = c("car", "cars", "Car ",
"Tire", "tyre", " breaks",
"brake pads ", " Steering wheel ",
"steering wheel", "door window", "door/window",
"bike", "Bicycle", "chain", "chains "),
METRIC_1 = sample(15:100, size = 15, replace = TRUE),
METRIC_1_CLASS = c("A", "B", "C"),
METRIC_2 = rnorm(15, 38.50, sd = 3),
METRIC_2_CLASS = c("I", "II", "III"))
# DT
#
# > DT
# ITEM METRIC_1 METRIC_1_CLASS METRIC_2 METRIC_2_CLASS
# 1: car 35 A 38.87161 I
# 2: cars 59 B 34.12781 II
# 3: Car 18 C 40.32863 III
# 4: Tire 29 A 38.78030 I
# 5: tyre 78 B 34.12089 II
# 6: breaks 72 C 36.40179 III
# 7: brake pads 99 A 39.32594 I
# 8: Steering wheel 47 B 45.04061 II
# 9: steering wheel 62 C 44.60871 III
# 10: door window 42 A 44.53798 I
# 11: door/window 96 B 40.25646 II
# 12: bike 49 C 39.59810 III
# 13: Bicycle 93 A 41.07434 I
# 14: chain 56 B 36.93384 II
# 15: chains 31 C 40.13403 III
对于＆＃39;项目＆＃39;专栏我想要
1 - 将外壳从下壳更换为上壳
2 - 移除前导或尾随空格，并用下划线替换中心空间
3 - 合并car，cars和Car的数据;合并Tire和tyre
4 - 处理前十行中的数据，因为它们是一个较大组的一部分，并且对最后4列执行相同操作。对于组合，METRIC_1是相加的，METRIC_2是相应分组的附加值
5 - 在METRIC_1_CLASS中替换为A = 100，B = 1000，C = 10000，METRIC_2_CLASS将被替换为类似。
我还想将密钥设置为ITEM和METRIC_1_CLASS，但我不确定在转换DT之前或之后是否应该这样做。
这部分代码似乎实现了一些更改
DT[, .(ITEM=toupper(trimws(ITEM)))]
# > DT[, .(ITEM=toupper(trimws(ITEM)))]
# ITEM
# 1: CAR
# 2: CARS
# 3: CAR
# 4: TIRE
# 5: TYRE
# 6: BREAKS
# 7: BRAKE PADS
# 8: STEERING WHEEL
# 9: STEERING WHEEL
# 10: DOOR WINDOW
# 11: DOOR/WINDOW
# 12: BIKE
# 13: BICYCLE
# 14: CHAIN
# 15: CHAINS
最终的DT应如下所示：
set.seed(57)
metric.2 <- DT$METRIC_2
DT <- data.table(ITEM = c("CAR", "TIRE", "BREAKS", "STEERING_WHEEL", "DOOR_WINDOW", "BIKE", "CHAIN"),
METRIC_1 = c(35+59+18, 29+78, 72+99, 47+62, 42+96, 49+93, 56+31),
METRIC_1_CLASS = c(11100, 1100, 10100, 11000, 1100, 10100, 11000),
METRIC_2 = c(sum(metric.2[1:3]), sum(metric.2[4:5]), sum(metric.2[6:7]), sum(metric.2[8:9]), sum(metric.2[10:11]),
sum(metric.2[12:13]), sum(metric.2[14:15])))
DT
# > DT
# ITEM METRIC_1 METRIC_1_CLASS METRIC_2
# 1: CAR 112 11100 113.32805
# 2: TIRE 107 11100 72.90119
# 3: BREAKS 171 11100 75.72772
# 4: STEERING_WHEEL 109 11100 89.64932
# 5: DOOR_WINDOW 138 11100 84.79444
# 6: BIKE 142 11100 80.67244
# 7: CHAIN 87 11100 77.06786
如果我从这个DT开始：
set.seed(57)
DT <- data.table(ITEM = c('CAR', 'CAR', 'CAR',
'TIRE', 'TIRE', 'BREAKS',
'BREAKS', 'STEERING_WHEEL', 'STEERING_WHEEL', 'DOOR_WINDOW',
'DOOR_WINDOW', 'BIKE', 'BIKE', 'CHAIN', 'CHAIN'),
METRIC_1 = sample(15:100, size = 15, replace = TRUE),
METRIC_1_CLASS = c(100, 1000, 10000),
METRIC_2 = rnorm(15, 38.50, sd = 3),
METRIC_2_CLASS = c("I", "II", "III")
)
DT
# > DT
# ITEM METRIC_1 METRIC_1_CLASS METRIC_2 METRIC_2_CLASS
# 1: CAR 35 100 38.87161 I
# 2: CAR 59 1000 34.12781 II
# 3: CAR 18 10000 40.32863 III
# 4: TIRE 29 100 38.78030 I
# 5: TIRE 78 1000 34.12089 II
# 6: BREAKS 72 10000 36.40179 III
# 7: BREAKS 99 100 39.32594 I
# 8: STEERING_WHEEL 47 1000 45.04061 II
# 9: STEERING_WHEEL 62 10000 44.60871 III
# 10: DOOR_WINDOW 42 100 44.53798 I
# 11: DOOR_WINDOW 96 1000 40.25646 II
# 12: BIKE 49 10000 39.59810 III
# 13: BIKE 93 100 41.07434 I
# 14: CHAIN 56 1000 36.93384 II
# 15: CHAIN 31 10000 40.13403 III
我可以这样做：
DT[, lapply(.SD, sum), by = "ITEM", .SDcols = c("METRIC_1", "METRIC_1_CLASS", "METRIC_2")]
# > DT[, lapply(.SD, sum), by = "ITEM", .SDcols = c("METRIC_1", "METRIC_1_CLASS", "METRIC_2")]
# ITEM METRIC_1 METRIC_1_CLASS METRIC_2
# 1: CAR 112 11100 113.32805
# 2: TIRE 107 1100 72.90119
# 3: BREAKS 171 10100 75.72772
# 4: STEERING_WHEEL 109 11000 89.64932
# 5: DOOR_WINDOW 138 1100 84.79444
# 6: BIKE 142 10100 80.67244
# 7: CHAIN 87 11000 77.06786
答案 0 :(得分：1)
手动很重，但是它完成了工作：
TextView loadingText = (TextView)findViewById(R.id.loadingText);
loadingText.setTextSize(36);
loadingText.setText("Morphing...");
Bitmap leftbm = ((BitmapDrawable)leftImage.getDrawable()).getBitmap();
Bitmap rightbm = ((BitmapDrawable)rightImage.getDrawable()).getBitmap();
Bitmap newbm = leftbm.copy(Bitmap.Config.ALPHA_8, true);
int[] pixels = new int[newbm.getHeight() * newbm.getWidth()];
newbm.getPixels(pixels, 0, newbm.getWidth(), 0, 0, newbm.getWidth(), newbm.getHeight());
if (!newbm.isMutable()) {
Log.d("mutable check", "" + newbm.isMutable());
return;
}
for (int i = 0; i < newbm.getWidth(); i++) {
for (int j = 0; j < newbm.getHeight(); j++) {
newbm.setHasAlpha(false);
newbm.setPixel(i, j, Color.rgb(0, 0, 255));
}
}
loadingText.clearComposingText();
((ImageView)findViewById(R.id.morphView)).setImageBitmap(newbm);