21st_century_c: eleventh chapter

Corretions.

21st_century_c/11/Makefile

@@ -2,7 +2,9 @@ CFLAGS = `pkg-config --cflags gsl` `pkg-config --cflags glib-2.0` -I../9
 CFLAGS += -Wall -g -std=c11 -fms-extensions
 LDLIBS = `pkg-config --libs gsl` `pkg-config --libs glib-2.0`
 
-OBJECTS = dict.a simple_cplx seamlessone seamlesstwo dict_use cetology groupabm
+OBJECTS = \
+	dict.a simple_cplx seamlessone seamlesstwo dict_use cetology \
+	groupabm groupabm.pdf groups.pdf
 all: $(OBJECTS)
 
 dict.a: keyval.o dict.o
@@ -18,10 +20,16 @@ moby:
 cetology: fstr.o ../9/string_utilities.o
 
 ../9/string_utilities.o:
-	make -C ../9/string_utilities.o
+	make -C ../9 string_utilities.o
 
 groupabm: groupabm.c groups.o apop.c
 
+groupabm.pdf: groupabm.tex
+	pdftex $^
+
+groups.pdf: groups.tex
+	pdftex $^
+
 test: moby
 	./simple_cplx
 	./seamlessone
@@ -32,4 +40,6 @@ test: moby
 clean:
 	rm -f \
 		$(OBJECTS) keyval.o dict.o complex.o fstr.o moby \
-		../9/string_utilities.o groupabm.c groups.c groups.o
+		../9/string_utilities.o \
+		groupabm{,.c,.idx,.log,.pdf,.scn,.tex,.toc} \
+		groups{.c,.idx,.log,.o,.pdf,.scn,.tex,.toc}

21st_century_c/11/groups.w

@@ -67,8 +67,8 @@ void group_exit(group_s * leaveme, gsl_vector * position) {
 distance to the groups. In the end, I wound up using the $L_3$ norm. The
 standard distance is the $L_2$ norm, aka Euclidean distance, meaning that the
 distance between $(x_1, y_1)$ and $(x_2, y_2)$ is
-$\sqrt{(x_1-x_2)^2+(y_1-y_2^2}$. This is $L_3$,
-${\sqrt[3]{(x_1-x_2)^3+(y_1-y_2)^3}$. This and the call to |apop_copy| above are
+$\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$. This is $L_3$,
+$\sqrt[3]{(x_1-x_2)^3+(y_1-y_2)^3}$. This and the call to |apop_copy| above are
 the only calls to the Apophenia library; you could write around them if you
 don't have that library on hand.