Quantize after invert, not in outputs or formatter.

src/pricehist/cli.py

@@ -101,6 +101,8 @@ def cmd_fetch(args):
 
     if args.invert:
         series = series.invert()
+    if args.quantize is not None:
+        series = series.quantize(args.quantize)
     if args.renamebase:
         series = series.rename_base(args.renamebase)
     if args.renamequote:
@@ -117,7 +119,6 @@ def cmd_fetch(args):
         thousands=if_not_none(args.formatthousands, default.thousands),
         symbol=if_not_none(args.formatsymbol, default.symbol),
         datesep=if_not_none(args.formatdatesep, default.datesep),
-        decimal_places=if_not_none(args.quantize, default.decimal_places),
     )
 
     print(output.format(series, source, fmt=fmt), end="")

src/pricehist/format.py

@@ -9,19 +9,3 @@ class Format:
     thousands: str = ""
     symbol: str = "rightspace"
     datesep: str = "-"
-    decimal_places: int = None
-
-    def quantize(self, num):
-        if self.decimal_places is None:
-            return num
-        else:
-            prec = getcontext().prec
-            digits = len(num.as_tuple().digits)
-            exponent = num.as_tuple().exponent
-
-            fractional_digits = -exponent
-            whole_digits = digits - fractional_digits
-            max_decimal_places = prec - whole_digits
-            chosen_decimal_places = min(self.decimal_places, max_decimal_places)
-
-            return num.quantize(Decimal("0." + ("0" * chosen_decimal_places)))

src/pricehist/outputs/beancount.py

@@ -8,7 +8,7 @@ class Beancount(BaseOutput):
         lines = []
         for price in series.prices:
 
-            amount_parts = f"{fmt.quantize(price.amount):,}".split(".")
+            amount_parts = f"{price.amount:,}".split(".")
             amount_parts[0] = amount_parts[0].replace(",", fmt.thousands)
             amount = ".".join(amount_parts)
 

src/pricehist/outputs/csv.py

@@ -8,7 +8,7 @@ class CSV(BaseOutput):
         lines = ["date,base,quote,amount,source,type"]
         for price in series.prices:
             date = str(price.date).replace("-", fmt.datesep)
-            amount_parts = f"{fmt.quantize(price.amount):,}".split(".")
+            amount_parts = f"{price.amount:,}".split(".")
             amount_parts[0] = amount_parts[0].replace(",", fmt.thousands)
             amount = fmt.decimal.join(amount_parts)
             line = ",".join(

src/pricehist/outputs/gnucashsql.py

@@ -15,16 +15,22 @@ class GnuCashSQL(BaseOutput):
         values_parts = []
         for price in series.prices:
             date = f"{price.date} {fmt.time}"
-            amount = fmt.quantize(price.amount)
             m = hashlib.sha256()
             m.update(
                 "".join(
-                    [date, series.base, series.quote, src, series.type, str(amount)]
+                    [
+                        date,
+                        series.base,
+                        series.quote,
+                        src,
+                        series.type,
+                        str(price.amount),
+                    ]
                 ).encode("utf-8")
             )
             guid = m.hexdigest()[0:32]
-            value_num = str(amount).replace(".", "")
-            value_denom = 10 ** len(f"{amount}.".split(".")[1])
+            value_num = str(price.amount).replace(".", "")
+            value_denom = 10 ** len(f"{price.amount}.".split(".")[1])
             v = (
                 "("
                 f"'{guid}', "

src/pricehist/outputs/ledger.py

@@ -9,7 +9,7 @@ class Ledger(BaseOutput):
         for price in series.prices:
             date = str(price.date).replace("-", fmt.datesep)
 
-            amount_parts = f"{fmt.quantize(price.amount):,}".split(".")
+            amount_parts = f"{price.amount:,}".split(".")
             amount_parts[0] = amount_parts[0].replace(",", fmt.thousands)
             amount = fmt.decimal.join(amount_parts)
 

src/pricehist/series.py

@@ -1,4 +1,5 @@
 from dataclasses import dataclass, field, replace
+from decimal import Decimal, getcontext
 
 from pricehist.price import Price
 
@@ -20,8 +21,30 @@ class Series:
             prices=[Price(date=p.date, amount=(1 / p.amount)) for p in self.prices],
         )
 
+    def quantize(self, decimal_places):
+        return replace(
+            self,
+            prices=[
+                replace(p, amount=self._quantize(p.amount, decimal_places))
+                for p in self.prices
+            ],
+        )
+
     def rename_base(self, new_base):
         return replace(self, base=new_base)
 
     def rename_quote(self, new_quote):
         return replace(self, quote=new_quote)
+
+    def _quantize(self, amount, decimal_places):
+        digits = len(amount.as_tuple().digits)
+        exponent = amount.as_tuple().exponent
+
+        fractional_digits = -exponent
+        whole_digits = digits - fractional_digits
+        max_decimal_places = getcontext().prec - whole_digits
+
+        chosen_decimal_places = min(decimal_places, max_decimal_places)
+        rounding = Decimal("0." + ("0" * chosen_decimal_places))
+
+        return amount.quantize(rounding)